Skeletal metastatic disease of the femur: results by management with intramedullary nailing.

PURPOSE OF THE STUDY This study aimed to analyse the outcome following intramedullary nailing for metastases of the femur in a large cohort with special regard to mechanical, implant associated complications and patient survival. Furthermore, we aimed to identify factors influencing the overall survival. MATERIAL AND METHODS All patients (n = 74) that underwent intramedullary nailing for metastatic disease of the femur between 2004 and 2008 and were retrospectively reviewed.

Quality of life and functional outcome of periprosthetic fractures around the knee following knee arthroplasty.

PURPOSE OF THE STUDY The present study aimed to analyse both, the functional outcome and quality of life after surgical treatment of periprosthetic fractures following TKA. MATERIAL AND METHODS A retrospective review of all periprosthetic fractures following knee arthroplasty which have been surgically treated at our institution between January 2005 and January 2012 was conducted. Beside epidemiologic data, type of surgery and postoperative complications were recorded.

The effects of age and gender on the lumbopelvic rhythm in the sagittal plane in 309 subjects.

Frequent upper body bending is associated with low back pain (LBP). The complex flexion movement, combining lumbar and pelvic motion, is known as "lumbopelvic rhythm" and can be quantified by dividing the change in the lumbar spine curvature by the change in pelvic orientation during flexion movement (L/P ratio). This parameter is clinically essential for LBP prevention, for diagnostic procedures and therapy; however, the effects of age and gender, in detail, are unknown.

Avoiding drainage after major hip surgery in children is a viable option: results from a retrospective comparative study.

Purpose: The use of closed-suction drainage systems to evacuate haematomas after surgical procedures is still common practice in many orthopaedic departments. However, no evidence to support the routine use of closed-suction drains in orthopaedic surgery exists. Post-operative handling and removal of the drain is particularly complicated in children.

Interfragmentary lag screw fixation in locking plate constructs increases stiffness in simple fracture patterns.

Background: The aim of the current biomechanical cadaver study was to quantify the influence of an additional lag screw on construct stiffness in simple fracture models at the distal femur stabilised with a locking plate.

Methods: For biomechanical testing paired fresh frozen human femora of 5 donors (mean age: 71 (SD 9) years) were chosen. Different locking plate configurations either with or without interfragmentary lag screw were tested under torsional load (2/4Nm/deg) or axial compression forces (500/1000N).

High-dose recombinant human bone morphogenetic protein-2 impacts histological and biomechanical properties of a cervical spine fusion segment: results from a sheep model.

The 'off-label' use of high-dose recombinant human bone morphogenetic protein-2 (rhBMP-2) in lumbar and cervical fusion leads to heterotopic bone formation and vertebral osteolysis. These radiographically assessed side-effects in patients were frequently associated with an over-dosage of BMP-2. However, little is so far known about the histological, functional or biomechanical tissue consequences of over-dosage of rhBMP-2 in these specific clinical situations.

Accuracy of simple plain radiographic signs and measures to diagnose acute scapholunate ligament injuries of the wrist.

Objective: To determine the accuracy of common radiological indices for diagnosing ruptures of the scapholunate (SL) ligament, the most relevant soft tissue injury of the wrist.

Methods: This was a prospective diagnostic accuracy study with independent verification of index test findings by a reference standard (wrist arthroscopy). Bilateral digital radiographs in posteroanterior (pa), lateral and Stecher's projection were evaluated by two independent expert readers.

Bicortical screw fixation provides superior biomechanical stability but devastating failure modes in periprosthetic femur fracture care using locking plates.

Purpose: The incidence of periprosthetic fractures is inevitably increasing. Sufficient stabilisation and proper screw placement next to large-volume implants remains difficult. Modern locking plates allow polyaxial, thus bicortical, screw placement around a prosthetic stem.

Working length of locking plates determines interfragmentary movement in distal femur fractures under physiological loading.

Background: This study aimed to investigate the influence of the screw location and plate working length of a locking plate construct at the distal femur on interfragmentary movement under physiological loading.

Methods: To quantitatively analyse the influence of plate working length on interfragmentary movements in a locking plate construct bridging a distal femur fracture, a finite element model based on CT (computed tomography) data was physiologically loaded and fracture gap conditions were calculated. Four working lengths with eight screw variations each were systemically analysed.

Adequate surgical treatment of periprosthetic femoral fractures following hip arthroplasty does not correlate with functional outcome and quality of life.

Purpose: This study aimed to analyse functional outcome and quality of life (QoL) after surgical treatment of periprosthetic femoral fractures (PPF) following total hip arthroplasty (THA).

Methods: This retrospective study assessed 67 patients from 2005 to 2012. Epidemiologic data, surgical details, comorbidities, deaths and postoperative complications were recorded.

Changes in hip geometry after selective dorsal rhizotomy in children with cerebral palsy.

Purpose: Hip development in children with spastic cerebral palsy (CP) may be different in comparison to that of typical developing children due to impaired motor function and altered lever arms. Selective dorsal rhizotomy (SDR) is known to reduce spasticity. It is postulated that it also improves mobility.

Qualifying stem cell sources: how to overcome potential pitfalls in regenerative medicine?

Regenerative medicine aims to replace lost cells and to restore damaged tissues and organs by either tissue-engineering approaches or stimulation of endogenous processes. Due to their biological properties, stem cells promise to be an effective source for such strategies. Especially adult multipotent stem cells (ASCs) are believed to be applicable in a broad range of therapies for the treatment of multifactorial diseases or age-related degeneration, although the molecular and cellular mechanisms underlying their regenerative function are often hardly described.

MRI evaluation of hip containment and congruency after closed reduction in congenital hip dislocation.

Background: Developmental dysplasia of the hip is the most common congenital skeletal disease. In its most severe form--dislocation--the treatment is directed at reducing the hip and establishing normal congruency between the femoral head and the acetabulum. Closed reduction with casting is a common primary treatment, where reduction is confirmed by magnetic resonance imaging (MRI).

In vivo tracking of segmental bone defect healing reveals that callus patterning is related to early mechanical stimuli.

This study addresses the hypothesis that callus formation, patterning, and mineralisation are impaired during the early phase of critical sized bone defect healing, and may relate to inter-fragmentary tissue strains within the bone defect area. Twenty four 12 week old Sprague Dawley rats were used for this study. They were divided into two groups defined by the femur bone defect size: (i) 1 mm resulting in normal healing (NH), and (ii) a large sized 5 mm defect resulting in critical healing (CH).

The durability of the intrascaphoid compression of headless compression screws: in vitro study.

Purpose: To test a new generation of compression screws: the Acumed Acutrak 2 Mini (AA; Acumed, Hillsboro, OR), the Stryker TwinFix (ST; Stryker, Kalamazoo, MI), and the Synthes 3.0 headless compression screw (SH; Synthes, Solothurn, Switzerland).

Methods: We used 40 fresh-frozen human scaphoids for this study.

Suture fixation versus cable cerclage of the tuberosities in shoulder arthroplasty-clinical and radiologic results.

Background: The most important individual parameter linked to functional outcome following hemiarthroplasty for fractures of the proximal humerus is anatomical healing of the tuberosities. The aim of our study was to evaluate whether the fixation method influences tuberosity healing and functional outcome.

Methods: Twenty-five consecutive patients with acute 4-part fractures of the proximal humerus were treated with hemiarthroplasty and cable fixation of the tuberosities.

BMI and gender do not influence surgical accuracy during minimally invasive total hip arthroplasty.

We investigated the accuracy of implant positioning during total hip arthroplasty (THA) through a minimally invasive approach in relation to body mass index (BMI) and gender by assessing 48 patients. Functional and radiological parameters were evaluated. BMI positively correlated with operation time (p=0.

Stabilization of fatigue fractures of the dorsal pelvis with a trans-sacral bar. Operative technique and outcome.

Introduction: Due to ageing of our population the number of fatigue fractures of the pelvic ring is steadily growing. These fractures are often treated with bed rest but may result in a disabling immobility with severe pain. An operative treatment is an option in these cases.

Age-related appearance of muscle trauma in primary total hip arthroplasty and the benefit of a minimally invasive approach for patients older than 70 years.

Old age is frequently associated with a poorer functional outcome after THA. This might be based upon muscular damage resulting from surgical trauma. Minimally invasive approaches have been widely promoted on the basis of the muscle sparing effect.

Influence of formalin fixation on the biomechanical properties of human diaphyseal bone.

Owing to the lack of fresh human bones, formalin-fixed specimens are frequently used in biomechanical testing. However, formalin fixation is assumed to affect the biomechanical properties of bone. The aim of this study was to compare axial and torsional stiffness and bone mineral density in fresh and embalmed human bones.

Development of treatment concepts for the use of botulinum toxin a in children with cerebral palsy.

The treatment of children with cerebral palsy with Botulinum toxin A injections is well established, safe and effective. However, a standardized injection strategy is still missing and the used dosage has escalated over the years. In the recent past, the recommended dosages in Europe were, however, reduced due to a better understanding of the relationship between dosage, severe side effects and the kind of anesthesia used.

Frontal plane alignment: an imageless method to predict the mechanical femoral-tibial angle (mFTA) based on functional determination of joint centres and axes.

Lower limb alignment is important for the internal loading conditions in the knee. In this study, we aimed to evaluate a new imageless, non-invasive method for quantifying frontal plane alignment by direct comparison against CT. To determine the mechanical femoral-tibial angle (mFTA), functional posture analysis was performed in 15 limbs (13 individuals) using previously published methods for the minimisation of skin marker artefact together with the functional identification of joints, and compared against a published regression method.

Three-dimensional stiffness in a thoracolumbar en-bloc spondylectomy model: a biomechanical in vitro study.

Background: In selected cases, en-bloc spondylectomy is the only option to reach wide resection margins for patients with malignant tumours of the thoracolumbar spine. These patients must be also provided a secure initial stabilization of the spine and this is the role of vertebral body replacements employed with posterior fixation systems. The aim of this study was to determine the postimplantation stiffness of a connected vertebral body replacement pedicle screw system in different implantation scenarios following an en-bloc spondylectomy.

Two-stage operative strategy without local antibiotic treatment for infected hip arthroplasty: clinical and radiological outcome.

Introduction: Two-stage revision hip surgery with insertion of local antibiotic carriers is the therapy of choice for infected hip arthroplasty. The disadvantages are the incalculable pharmacokinetics of the antibiotic, with the danger of resistance and sensitisation. In a retrospective study, the effectiveness of a two-stage revision strategy done without local antibiotics was to be investigated.