Marcin Domzalski

Risk factors for Anterior Cruciate Ligament injury in skeletally immature patients: analysis of intercondylar notch width using Magnetic Resonance Imaging.

The necessity for identification of risk factors for Anterior Cruciate Ligament, ACL injury has challenged many investigators. Many authors have reported lower Notch Width Index, NWI measured on radiographs in patients with midsubstance ACL lesions compared to control groups. Since a narrow intercondylar notch has been implicated as a possible risk factor related to ACL injury we decided to compare NWI measured on MRI scans between age-matched groups with acute ACL injury with those of the normal population. The purpose of this study was to measure intercondylar notch width on MRI scans in an immature population to determine if there was a difference between the population with ACL tears and a control group. We also wanted to assess age as a risk factor in an ACL injury population. We retrospectively analysed the MRI scans of 46 patients with ACL injuries and 44 patients with normal MRI findings who served as a control group for NWI measurements. For the ACL injury group we collected information from medical charts including age at the time of injury, gender, mechanism of injury, type of activity practised at the time of injury and prevalence of meniscal injury. Demographic data of the control group were comparable with those from the study group. We found a statistically significant (p < 0.001) difference in the mean value of the intercondylar notch width between normal knees (0.2691) and the ACL injury population (0.2415). In the ACL injury group we did not find differences in NWI values with regard to gender, involved side, mechanism of injury and type of sport practised at the time of injury. A narrower intercondylar notch was found to be associated with the risk of ACL rupture in an immature population. The young group of athletes with ACL injury needs further study to prospectively assess the risk of knee injuries.

Lateral Acetabular Growth Stimulation Following a Labral Support Procedure in Legg-Calvé-Perthes Disease

BACKGROUND The main goal of containment treatment in cases of Legg-Calvé-Perthes disease is to prevent hip deformity, which leads to arthritis in adulthood. Recently, the shelf arthroplasty (the labral support procedure) has been proposed as a method of containment. The purpose of the present study was to evaluate growth stimulation of the acetabulum in patients with unilateral Legg-Calvé-Perthes disease by measuring acetabular depth and height following treatment with the labral support procedure. Uninvolved, contralateral hips and hips that were treated with proximal femoral varus osteotomy were used to compare growth. METHODS Sixty-five consecutive patients with unilateral Legg-Calvé-Perthes disease that had been treated with the labral support procedure (forty-nine) or a proximal femoral varus osteotomy (sixteen) were evaluated on the basis of radiographic and clinical data that had been obtained at the time of surgery as well as at one, three, and five years after surgery. Acetabular dimensions (depth, height, and total depth with shelf) were measured and, to eliminate radiographic magnification error, the data were expressed in ratios between the involved and uninvolved sides. RESULTS Preoperatively, both surgical groups were comparable. Acetabular depth indexes at the time of surgery were not different between the groups (p = 0.46). At one, three, and five years postoperatively, the mean depth indexes in the labral support group were significantly higher than those in the proximal femoral varus osteotomy group (F = 5.417, p = 0.001), and trend analysis showed a significant quadratic effect over time in the labral support procedure group (F = 13.132, p = 0.001). The acetabular height indexes at the time of surgery were not different between groups and showed 11% to 13% acetabular overgrowth. The acetabular height indexes in both groups remained unchanged at the time of follow-up (F = 2.82, p = 0.1). The total depth index showed decreasing linear trend values over the period studied (F = 35.115, p = 0.001). CONCLUSIONS Overgrowth of the acetabulum occurs naturally and early in the course of Legg-Calvé-Perthes disease and is more pronounced in terms of height. The labral support procedure induces additional lateral growth of the true acetabulum (excluding the shelf) for three years following surgery, whereas a proximal femoral varus osteotomy does not. Thus, beneficial effects of the labral support procedure are lateral acetabular growth stimulation, prevention of subluxation, and shelf resolution after femoral epiphyseal reossification. LEVEL OF EVIDENCE Therapeutic Level III. See Instructions to Authors for a complete description of levels of evidence.

Avascular necrosis after surgical treatment for developmental dysplasia of the hip

We reviewed the medical records of 101 patients with developmental dysplasia of the hip who were treated with Dega’s (102 hips), or Salter’s (42 hips) osteotomy preceded by open reduction and femoral intertrochanteric osteotomy. The minimal follow-up was 17 years. At the last follow-up, there were proximal femoral growth disturbances in 52 hips (36%). In 20 hips, the disturbances were graded as mild and in six as severe. We found significantly better clinical and radiological results in hips without avascular changes. Risk factors for the development of avascular necrosis were: involvement of the left side and surgical treatment initiated after 2 years of age without pre-operative traction and without femoral shaft shortening. We found that the incidence of avascular necrosis increased with the length of follow-up. The avascular necrosis influenced both clinical and radiological results.RésuméNous avons examiné les registres médicaux de 101 malades avec une dysplasie congénitale de la hanche qui ont été traitée par ostéotomie de Dega (102 hanches) ou Salter (42 hanches) précédé par réduction ouverte et ostéotomie fémorale intertrochantérienne. Le suivi minimal était de 17 ans. Àu dernier recul il y avait des troubles de croissance des fémurs proximaux dans 52 hanches (36%). Dans 20 hanches les troubles ont été notés comme discrets et en six comme sévères. Nous avons trouvé des résultats cliniques et radiologiques bien meilleurs dans les hanches sans troubles vasculaires. Les facteurs du risque pour le développement d’une nécrose avasculaire étaient: l’affection du côté gauche, le traitement chirurgical commencé après l’âge de 2 ans sans traction préopératoire et sans raccourcissement de la diaphyse fémorale. Nous avons trouvé que la fréquence des nécroses avasculaires a augmenté avec la durée d’observation. La nécrose avasculaire a influencé les résultats cliniques et radiologiques.

Effects of Hydrostatic Loading on a Self-Aggregating, Suspension Culture–Derived Cartilage Tissue Analog

Objective: Many approaches are being taken to generate cartilage replacement materials. The goal of this study was to use a self-aggregating suspension culture model of chondrocytes with mechanical preconditioning. Design: Our model differs from others in that it is based on a scaffold-less, self-aggregating culture model that produces a cartilage tissue analog that has been shown to share many similarities with the natural cartilage phenotype. Owing to the known loaded environment under which chondrocytes function in vivo, we hypothesized that applying force to the suspension culture–derived chondrocyte biomass would improve its cartilage-like characteristics and provide a new model for engineering cartilage tissue analogs. Results: In this study, we used a specialized hydrostatic pressure bioreactor system to apply mechanical forces during the growth phase to improve biochemical and biophysical properties of the biomaterial formed. We demonstrated that using this high-density suspension culture, a biomaterial more consistent with the hyaline cartilage phenotype was produced without any foreign material added. Unpassaged chondrocytes responded to a physiologically relevant hydrostatic load by significantly increasing gene expression of critical cartilage molecule collagen and aggrecan along with other cartilage relevant genes, CD44, perlecan, decorin, COMP, and iNOS. Conclusions: This study describes a self-aggregating bioreactor model without foreign material or scaffold in which chondrocytes form a cartilage tissue analog with many features similar to native cartilage. This study represents a promising scaffold-less, methodological advancement in cartilage tissue engineering with potential translational applications to cartilage repair.

Fractures of the distal humeral metaphyseal-diaphyseal junction in children.

Background: To our knowledge, there is no report in the English-language literature of metaphyseal-diaphyseal junction fractures of the distal humerus in children. The purpose of this study was to review our experience with this uncommon fracture. Methods: Between 1998 and 2004, 422 displaced supracondylar humerus fractures underwent operative reduction and fixation at our institution. A retrospective review of medical records and radiographs revealed that 14 (3.3%) of these fractures occurred at the metaphyseal-diaphyseal junction just proximal to the olecranon fossa. In 8 patients, the fracture line was oblique (group A), and in 6 patients, the fracture line was transverse (group B). Results: Average age at the time of fracture was 4.9 years (range, 1.5-10 years). All patients were treated by closed reduction and Kirschner wire fixation and had at least 1-year follow-up. In group A, operative time for reduction and fixation was significantly increased in comparison to the 408 remaining supracondylar humerus fractures. However, the clinical course in group A was uncomplicated, and no loss of fixation at follow-up was noted. The operative time in group B was even longer. These fractures were more problematic as loss of fixation occurred in 5 of the 6 patients, 4 occurring in the sagittal plane. In addition, multiple complications arose in group B including reoperation, cubitus varus, pin migration, and prolonged loss of motion. Conclusion: Metaphyseal-diaphyseal junction fractures of the distal humerus in children are rare but can be problematic. The transverse fracture pattern requires additional attention in the operating room with optimal pin fixation. Close postoperative follow-up is necessary. The oblique fracture pattern, while requiring increased time in the operating room for reduction and fixation, is typically stable with the usual fixation used for supracondylar humerus fractures. In summary, metaphyseal-diaphyseal junction fractures of the distal humerus are uncommon elbow fractures in children that should be differentiated from the more common supracondylar humerus fracture for optimal outcomes. Level of Evidence: Therapeutic level 4 (case series).

Fractures of the distal tibial metaphysis in children : Patterns of injury and results of treatment

Background: Fractures of the tibia are common in children. Fractures of the distal tibial metaphysis have been only described in fracture texts without reference to a peer-reviewed study. The purpose of the present study was to review this fracture pattern and report the results of treatment. Methods: The medical records and radiographs of children seen at our institution with a fracture of the tibia were reviewed. The patients with fractures of the distal tibial metaphysis who had been followed until healing were included. Fractures of the distal tibial diaphysis, toddlers fractures, and pathologic fractures were excluded. Results: Twenty-six children met these criteria and were included in the study. The mechanism of injury was indirect in 13 fractures and direct in 12 fractures. In 1 patient, the mechanism of injury was unknown. The main cause of indirect injury was fall (11 cases). The most common was the transverse type of fracture (14 patients) followed by the oblique type (11 patients). Only 8 cases were nondisplaced. Valgus angulation was usually associated with a recurvatum deformation, whereas varus angulation was associated with procurvatum angulation. These patterns were present in 14 patients. We observed shorter healing time when the fracture was oblique than transverse. Children with the oblique pattern of injury were younger than children with a transverse fracture. Conclusions: The patterns of displacement of the distal tibial metaphyseal fractures reported in our study vary from those presented in textbooks. Distal tibial metaphyseal fractures can present with 2 types of displacement: valgus recurvatum and varus procurvatum. Fractures of the fibula always present with the same pattern as the tibia. Primary union of the distal tibial metaphyseal fracture may be expected in all cases regardless of the type of fracture, age, and gender. Level of evidence: IV case series.

Growth arrest of the proximal tibial physis with recurvatum and valgus deformity of the knee

Two cases of asymmetrical closure of the proximal tibial epiphysis without a clear aetiological factor were presented. In both cases premature closure of the growth plate resulted in progressive recurvatum and valgus deformity of the knee with leg length discrepancy. The correction of deformity was obtained using Taylor Spatial frame with excellent results at 2 years follow-up. We hypothesize that repetitive trauma or chronic overloading during sports activities might be a factor of growth arrest in reported cases. Orthopedic surgeons should be aware of the possibility of subtle physeal injuries, causing angular deformities, in the cases of even minor knee trauma in skeletally immature population.

Pectoralis major release to improve shoulder abduction in children with cerebral palsy.

The aim of our study was to evaluate the surgical results after pectoralis major muscle release in children with cerebral palsy and to assess a caregivers satisfaction in patients care after this procedure. Twenty-one shoulders in 13 patients were analyzed at least 12 months after surgery. All but 1 patient involved in our study had quadriplegic type of cerebral palsy involvement. In 17 limbs, only pectoralis release was performed; in 4 limbs, latissimus dorsi release was added. After clinical examination, a questionnaire was used to determine the caregivers assessment. The passive range of abduction and flexion was maintained at an angle greater than 90 degrees in 10 patients. External rotation was restricted in 6 patients. All caregivers would recommend this surgery to another patient. All but one reported improvement in care of the patients after surgery. The indication for this surgical procedure is limited only to the selected cerebral palsy cases in which custodial care is impaired by shoulder adduction contracture. The 2 main indications for the procedure are the limitations in the ability to bathe the axilla and the difficulty in dressing.

The proximal femoral growth plate in Perthes disease.

We hypothesized the extent of involvement of the proximal femoral growth plate in Perthes disease determined the final radiographic outcome after containment by shelf acetabulo-plasty. We retrospectively evaluated the extent of growth plate involvement using a modified version of the method described by Yasuda and Tamura. In our modification, we used only the epiphyseal border for measurements, which was clearly visible as a thin white line, unlike Yasuda and Tamura who used the metaphyseal and epiphyseal borders. We could not clearly demarcate the metaphyseal border in the radiographs of our patient population between 1944 and 1998, which consisted of 69 patients who had surgery at a mean age of 9 years (range, 6.0-14.1 years). From these measurements, we formulated an index termed “growth plate involvement.” Radiographic results were classified as described by Stulberg et al A growth plate involvement index less than 0.25 resulted in a good radiographic outcome. We found 93.2% sensitivity and 100% specificity in predicting Stulbergs outcomes. The growth plate involvement index is a reliable and reproducible measurement method and may be used prospectively as a useful prognostic factor to predict radiographic outcomes after containment acetabuloplasty.Level of Evidence: Level II, prognostic study (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Thickening of the knee joint cartilage in elite weightlifters as a potential adaptation mechanism

Thickening and increase of area of cartilage have been proposed as two alternative mechanisms of cartilage functional adaptation. The latter has been reported in endurance sportsmen. In weightlifters, extreme strain applied to the articular surfaces can result in other forms of adaptation. The aim of this research is to determine whether cartilage thickness is greater in elite weightlifters than in physically inactive men. Weightlifters (13) and 20 controls [age and body mass index (BMI) matched] underwent knee Magnetic Resonance Imaging (MRI). A single sagittal slice of the knee was taken and cartilage thickness was measured in five and six regions of the medial and lateral femoral condyles, respectively. The analyzed segments represented weight‐bearing and nonweight‐bearing regions. The tibia cartilage in the weight‐bearing area was also measured. The time of training onset and its duration in the weightlifter group were recorded. The cartilage was found to be significantly thicker in weightlifters in most of the analyzed regions. The distribution of cartilage thickness on the medial and lateral femoral condyles was similar in both groups. The duration of training was not associated with cartilage thickness, but the time of training onset correlated inversely with cartilage thickness. It is possible that in high‐strain sports, joint cartilage can undergo functional adaptation by thickening. Thus, mechanical loading history could exert a postnatal influence on cartilage morphology. Clin. Anat. 27:920–928, 2014.