Management of Dorsal Bunion in Nonambulatory Adolescents with Cerebral Palsy: A Retrospective Cohort Study.

Background: A dorsal bunion may occur in nonambulatory adolescents with cerebral palsy (CP) and a Gross Motor Function Classification System (GMFCS) level of IV or V. The deformity can cause pain, skin breakdown, and difficulty wearing shoes and braces. A consensus on the biomechanics and surgical management of dorsal bunions in persons with severe CP has not been established.

A lateral extra-articular tenodesis without additional hardware: Surgical technique and biomechanical comparison with an anatomic anterolateral ligament reconstruction in the augmentation of anterior cruciate ligament reconstruction.

Background: The aims of this study were to describe a lateral extra-articular tenodesis (LET) using no additional hardware and compare the tibiofemoral kinematics of anterior cruciate ligament (ACL) reconstruction augmented with either the LET or a standard anatomic anterolateral ligament (ALL) reconstruction using intra-tunnel fixation.

Methods: Ten cadaveric knees were mounted on a robotic testing system and underwent a kinematic assessment of anterior tibial translation and internal tibial rotation under a simulated pivot-shift in the following states: ACL-intact, ACL-sectioned, ACL-sectioned/anterolateral complex (ALC)-sectioned, ACL-reconstructed/ALC-sectioned, ACL-reconstructed/ALL-reconstructed, and ACL-reconstructed/LET. For the LET, an iliotibial autograft was passed under the fibular collateral ligament and secured to the femur with the pull sutures of the ACL reconstruction femoral cortical suspensory fixation device, positioned at the distal ridge of Kaplan's fibers.

Arthrodesis of the first metatarsophalangeal joint for severe hallux valgus in adolescents with cerebral palsy: A retrospective comparison study of three surgical techniques.

Purpose: We compared the outcomes of arthrodesis of the first metatarsophalangeal joint for severe hallux valgus in 31 adolescents with cerebral palsy, using three different methods of fixation: K-wires, non-locking plates, and locking plates.

Methods: Clinical outcomes included time to weight-bearing, fusion rates and surgical complications. Radiographic assessment included comparing pre- and post-operative hallux valgus angles, intermetatarsal angles, interphalangeal angles, and lateral metatarsophalangeal angles.

Double-Bundle Anterior Cruciate Ligament Reconstruction With Primary Repair and Hamstring Autograft Augmentation.

The optimal treatment of a ruptured anterior cruciate ligament (ACL) restores the patient's native anatomy and biomechanics as close to normal as possible. The purpose of this technical note is to describe an ACL reconstruction technique in which a double-bundle concept is used, wherein one bundle contains repaired ACL tissue and the second bundle contains a hamstring autograft, and each bundle is tensioned independently. Even in chronic cases, this technique allows for incorporation of the native ACL because, more often than not, there is sufficient tissue of good quality available for repair of one bundle.

Seasonal Variation in Parental Satisfaction With Pediatric Orthopaedics.

Background: The degree of parental satisfaction with health care is determined by the family's characteristics and expectations. Many aspects of human physiology and behavior have seasonal rhythms. The purpose of the present study was to determine whether parental satisfaction scores vary across the year in a pediatric orthopaedic outpatient population.

[Anterior cruciate ligament rupture in children: A growing problem].

The number of knee injuries in young children has risen sharply in recent years, due to more intensive participation in sporting activities by children at an increasingly lower age. This has led to more anterior cruciate ligament (ACL) ruptures. An ACL rupture has major consequences for the young athlete, but diagnosing this injury in a child can be difficult due to pain and anxiety.

The Influence of Aspiration Volume on the Number of Osteoblastic Progenitors Obtained From Bone Marrow in Children.

Background: Autologous bone marrow aspirates are utilized to treat various conditions in children. The biological value of bone marrow aspirate depends on the concentration of competent osteoblastic progenitors present in the aspirate. It has been shown in adults that increasing bone marrow aspiration volume beyond 2 mL decreases the concentration of osteoblast progenitor cells because of dilution of the sample with peripheral blood.

The Medial Patellofemoral Ligament Is a Dynamic and Anisometric Structure: An In Vivo Study on Length Changes and Isometry.

Background: Medial patellofemoral ligament (MPFL) reconstruction is associated with a high rate of complications, including recurrent instability and persistent knee pain. Technical errors are among the primary causes of these complications. Understanding the effect of adjusting patellofemoral attachments on length change patterns may help surgeons to optimize graft placement during MPFL reconstruction and to reduce graft failure rates.

The Occurrence of Meniscal and Chondral Injury in Two-Stage Revision Anterior Cruciate Ligament Reconstruction: A Consecutive Case Series.

Two-stage revision anterior cruciate ligament (ACL) reconstruction is an effective way to revise suboptimal tunnel-placement allowing for proper graft fixation. However, prolonged increased laxity of the knee may increase the risk of meniscal or chondral injury. It was hypothesized that no additional meniscal or chondral lesions occur in between the two stages of the two-stage revision ACL reconstruction.

Anatomic is better than isometric posterior cruciate ligament tunnel placement based upon in vivo simulation.

Purpose: To elucidate the effects of various tibial and femoral attachment locations on the theoretical length changes and isometry of PCL grafts in healthy knees during in vivo weightbearing motion.

Methods: The intact knees of 14 patients were imaged using a combined magnetic resonance and dual fluoroscopic imaging technique while the patient performed a quasi-static lunge (0°-120° of flexion). The theoretical end-to-end distances of the 3-dimensional wrapping paths between 165 femoral attachments, including the anatomic anterolateral bundle (ALB), central attachment and posteromedial bundle (PMB) of the PCL, connected to an anterolateral, central, and posteromedial tibial attachment were simulated and measured.

The effect of ACL deficiency on the end-to-end distances of the tibiofemoral ACL attachment during in vivo dynamic activity.

Purpose: To evaluate the effect of ACL deficiency on the in vivo changes in end-to-end distances and to determine appropriate graft fixation angles for commonly used tunnel positions in contemporary ACL reconstruction techniques.

Methods: Twenty-one patients with unilateral ACL-deficient and intact contralateral knees were included. Each knee was studied using a combined magnetic resonance and dual fluoroscopic imaging technique while the patients performed a dynamic step-up motion (~50° of flexion to extension).

Analysis of the Scalability of UWB Indoor Localization Solutions for High User Densities.

Radio frequency (RF) technologies are often used to track assets in indoor environments. Among others, ultra-wideband (UWB) has constantly gained interest thanks to its capability to obtain typical errors of 30 cm or lower, making it more accurate than other wireless technologies such as WiFi, which normally can predict the location with several meters accuracy. However, mainly due to technical requirements that are part of the standard, conventional medium access strategies such as clear channel assessment, are not straightforward to implement.

Symptomatic hallux valgus and dorsal bunion in adolescents with cerebral palsy: clinical and biomechanical factors.

Aim: The prevalence of severely symptomatic deformities of the first metatarsophalangeal (MTP) joint in adolescents with cerebral palsy (CP) requiring arthrodesis is unknown. Recent literature regarding these deformities is limited. We studied the presentation of severe, symptomatic deformities of the first ray in a large population of children and adolescents with CP and their association with gross motor function, CP subtype, and other musculoskeletal deformities.

An In Vivo Prediction of Anisometry and Strain in Anterior Cruciate Ligament Reconstruction - A Combined Magnetic Resonance and Dual Fluoroscopic Imaging Analysis.

Purpose: To evaluate the in vivo anisometry and strain of theoretical anterior cruciate ligament (ACL) grafts in the healthy knee using various socket locations on both the femur and tibia.

Methods: Eighteen healthy knees were imaged using magnetic resonance imaging and dual fluoroscopic imaging techniques during a step-up and sit-to-stand motion. The anisometry of the medial aspect of the lateral femoral condyle was mapped using 144 theoretical socket positions connected to an anteromedial, central, and posterolateral attachment site on the tibia.

An in Vivo Simulation of Isometry of the Anterolateral Aspect of the Healthy Knee.

Background: To assess the isometry of theoretical lateral extra-articular reconstruction (LER), we evaluated theoretical grafts attached to various points on the lateral femoral condylar area and to either Gerdy's tubercle or the anatomic attachment site of the anterolateral ligament to the tibia.

Methods: In 18 subjects, healthy knees with no history of either injury or surgery involving the lower extremity were studied. The subjects performed a sit-to-stand motion (from approximately 90° of flexion to full extension), and each knee was studied using magnetic resonance and dual fluoroscopic imaging techniques.

In Vivo Anterolateral Ligament Length Change in the Healthy Knee During Functional Activities-A Combined Magnetic Resonance and Dual Fluoroscopic Imaging Analysis.

Purpose: To measure the in vivo anterolateral ligament (ALL) length change in healthy knees during step-up and sit-to-stand motions.

Methods: Eighteen healthy knees were imaged using magnetic resonance and dual fluoroscopic imaging techniques during a step-up and sit-to-stand motion. The ALL length change was measured using the shortest three-dimensional wrapping path, with its femoral attachment located slightly anterior-distal (ALL-Claes) or posterior-proximal (ALL-Kennedy) to the fibular collateral ligament attachment.

In Vivo Length Changes of the Anterolateral Ligament and Related Extra-articular Reconstructions.

Background: Both anatomic anterolateral ligament (ALL) and nonanatomic anterolateral reconstructions are performed to improve the stability of anterior cruciate ligament (ACL)-deficient patients. However, the in vivo length change patterns and isometry of these anterolateral reconstructions are unknown.

Purpose: To measure the theoretical length change patterns of the ALL and various anterolateral extra-articular reconstructions in healthy and ACL-deficient knees during in vivo weightbearing flexion.

Anterolateral Extra-articular Soft Tissue Reconstruction in Anterolateral Rotatory Instability of the Knee.

Anterolateral rotatory instability (ALRI) occurs after injury to the anterior cruciate ligament (ACL) and the anterolateral structures of the knee. We present a technique for anterolateral extra-articular soft-tissue (ALES) reconstruction of the knee that can be used in revision ACL reconstruction cases, cases of persistent ALRI after adequate ACL reconstruction, and cases with severe ALRI after primary ACL rupture. The surgeon performs ALES reconstruction with a strip of iliotibial tract autograft while respecting the anatomic origin and insertion of the anterolateral ligament.

Human mobility monitoring in very low resolution visual sensor network.

This paper proposes an automated system for monitoring mobility patterns using a network of very low resolution visual sensors (30 × 30 pixels). The use of very low resolution sensors reduces privacy concern, cost, computation requirement and power consumption. The core of our proposed system is a robust people tracker that uses low resolution videos provided by the visual sensor network.

Complications and institutionalization are almost doubled after second hip fracture surgery in the elderly patient.

Purpose: To determine patient and hip fracture characteristics, early postoperative complication rate, and need for institutionalization at the time of discharge from the hospital in patients treated for a second contralateral hip fracture.

Methods: During a 6-year period (2003-2009), 71 patients (60 women and 11 men; age range, 54-94 years) underwent first hip fracture surgery and subsequent contralateral hip fracture surgery at our hospital. Variables, including age, gender, American Society of Anesthesiologists classification (ASA), AO fracture classification, time between both hip fractures, rate and severity of early postoperative complications, and destination of discharge were obtained from the electronic medical records.

Bone marrow edema lesions in the professional runner.

Background: The clinical significance of an incidental finding of bone marrow edema (BME) on MRI in professional runners is poorly understood.

Purpose: To investigate the prevalence and clinical and radiological progression of BME lesions in professional runners who consider themselves to be asymptomatic.

Study Design: Case series; Level of evidence, 4.

Tibiofemoral cartilage contact biomechanics in patients after reconstruction of a ruptured anterior cruciate ligament.

We investigated the in vivo cartilage contact biomechanics of the tibiofemoral joint in patients after reconstruction of a ruptured anterior cruciate ligament (ACL). A dual fluoroscopic and MR imaging technique was used to investigate the cartilage contact biomechanics of the tibiofemoral joint during in vivo weight-bearing flexion of the knee in eight patients 6 months following clinically successful reconstruction of an acute isolated ACL rupture. The location of tibiofemoral cartilage contact, size of the contact area, cartilage thickness at the contact area, and magnitude of the cartilage contact deformation of the ACL-reconstructed knees were compared with those previously measured in intact (contralateral) knees and ACL-deficient knees of the same subjects.

Surgical technique: aperture fixation in PCL reconstruction: applying biomechanics to surgery.

Background: Biomechanical studies suggest reducing the effective graft length during transtibial posterior cruciate ligament (PCL) reconstruction by augmenting the distal tibial fixation with a proximal screw near the tibial tunnel aperture could increase graft stiffness and provide a more stable reconstruction. However, it remains unknown to what extent this mechanical theory influences in vivo graft performance over time.

Surgical Technique: We developed a technique to augment tibial distal fixation with a proximal screw near the tibial tunnel aperture to shorten the effective graft length and increase graft stiffness.

Tunnel position and graft orientation in failed anterior cruciate ligament reconstruction: a clinical and imaging analysis.

Purpose: It has been reported that technical error in positioning the graft tunnel is the most common problem in anterior cruciate ligament (ACL) reconstruction. The objective of this study was to quantitatively evaluate femoral and tibial tunnel positions and intra-articular graft orientation of primary ACL reconstruction in patients who had undergone revision ACL reconstruction. We postulated that this patient cohort had a nonanatomically positioned tunnel and graft orientation.