Relevance of instrumented gait analysis in the prediction of the rebound phenomenon after guided growth intervention.

Predictors of rebound after correction of coronal plane deformities using temporary hemiepiphysiodesis (TH) are not well defined. The following research questions were tested: (1) Is the dynamic knee joint load useful to improve rebound prediction accuracy? (2) Does a large initial deformity play a critical role in rebound development? (3) Are BMI and a young age risk factors for rebound? Fifty children and adolescents with idiopathic knee valgus malalignment were included. A deviation of the mechanical femorotibial angle (MFA) of ≥ 3° into valgus between explantation and the one-year follow-up period was chosen to classify a rebound.

Elastic Compression Dressing after Total Hip Replacement Slightly Reduces Leg Swelling: A Randomized Controlled Trial.

: Even minor adverse reactions after total hip replacement (THR), including lymphedema, postoperative leg swelling, and blood loss, compromise patient comfort in times of minimally invasive fast-track surgery. Compression dressings are commonly used in surgical practice to reduce swelling or blood loss. However, the use of spica hip compression dressings after primary THR is controversial, and prospective studies are lacking.

Spacer rotation technique allows precise evaluation of gap balance in total knee arthroplasty.

The symmetry of the flexion and extension gap influences the functional and long-term outcome after total knee arthroplasty (TKA). Most surgeons check it by applying varus and valgus stress using spacers. This technique has limited accuracy and could be easily extended by rotational movement of the spacer.

Optimized reamer geometry for controlled reaming of the proximal femur.

Preparation of the femoral proximal medullary cavity by reaming is essential for intramedullary nail osteosynthesis and hip revision arthroplasty. The use of reamers sometimes exerts high torsional forces on the bone. Design and direction of rotation of the reamer are potential influencing factors.

Force transmission capacity of the lower limb during walking of amputees with bone-anchored prostheses compared with socket prostheses and persons with hip replacements.

Background: Restoring the ability to walk with a prosthesis is considered a fundamental rehabilitation goal after transfemoral amputation. An essential prerequisite for achieving this goal is adequate force transmission between the prosthesis and the body. Does bone anchorage of an artificial limb permit a more normal force transmission?

Methods: Data of 15 healthy subjects, nine amputees fitted with bone-anchored prostheses, nine amputees using socket prostheses, and 18 patients with a total hip replacement were included in this multicenter, observational study.

Forgivingness of an Anteromedially Positioned Small Locked Plate for High Tibial Osteotomy in Case of Overcorrection and Lateral Hinge Fracture.

High tibial osteotomy (HTO) represents a sensible treatment option for patients with moderate unicondylar osteoarthritis of the knee and extraarticular malalignment. The possibility of a continuously variable correction setting and a surgical approach low in complications has meant that the medial opening osteotomy has prevailed over the past decades. The objective of the present study was to determine whether anteromedially positioned small plates are nevertheless forgiving under biomechanically unfavourable conditions (overcorrection and lateral hinge fracture).

Single Application of Low-Dose, Hydroxyapatite-Bound BMP-2 or GDF-5 Induces Long-Term Bone Formation and Biomechanical Stabilization of a Bone Defect in a Senile Sheep Lumbar Osteopenia Model.

Effects of hydroxyapatite (HA) particles with bone morphogenetic BMP-2 or GDF-5 were compared in sheep lumbar osteopenia; in vitro release in phosphate-buffered saline (PBS) or sheep serum was assessed by ELISA. Lumbar (L) vertebral bone defects (Ø 3.5 mm) were generated in aged, osteopenic female sheep ( = 72; 9.

Impaction bone grafting for segmental acetabular defects: a biomechanical study.

Introduction: Implant loosening is the most common indication for revision after total hip arthroplasty and is associated with progressive bone destruction. Contained defects can be treated with impaction bone grafting (IBG). Segmental defects are successfully restored with metal augmentation.

Minimally Invasive Internal Fixation of Femoral Shaft Fractures-A Biomechanical Study with a Disruptive Technique.

(1) Background: In polytrauma patients, femur fractures are usually stabilised by external fixation for damage control, later being treated with definitive plate or nail osteosynthesis. Screw/rod systems established in spinal surgery might be inserted for internal fixation, providing sufficient fracture stability that subsequent intervention is unnecessary. This was to be investigated biomechanically.

Mobile Robot-Based Gait Training after Total Hip Arthroplasty (THA) Improves Walking in Biomechanical Gait Analysis.

Unlabelled: There are multiple attempts to decrease costs in the healthcare system while maintaining a high treatment quality. Digital therapies receive increasing attention in clinical practice, mainly relating to home-based exercises supported by mobile devices, eventually in combination with wearable sensors. The aim of this study was to determine if patients following total hip arthroplasty (THA) could benefit from gait training on crutches conducted by a mobile robot in a clinical setting.

Temporal and spatial relationship between gluteal muscle Surface EMG activity and the vertical component of the ground reaction force during walking.

Background: Optimized temporal and spatial activation of the gluteal intermuscular functional unit is essential for steady gait and minimized joint loading.

Research Question: To analyze the temporal relationship between spatially resolved surface EMG (SEMG) of the gluteal region and the corresponding ground reaction force (GRF).

Methods: Healthy adults (29♀; 25♂; age 62.

Feasibility Analysis of a Novel Method for the Estimation of Local Bone Mechanical Properties: A Preliminary Investigation of Different Pressure Rod Designs on Synthetic Cancellous Bone Models.

Background: Whilst traumatology around elderly population becomes more and more popular nowadays, the knowledge of local bone quality prior to osteosynthesis is of paramount importance. Assessment of the local bone mechanical properties provides essential information related to implant stability and can support treatment strategies in a timely manner. In the acute setting, dual-energy X-ray absorptiometry and quantitative computer tomography cannot be used routinely, and up till now no known intraoperative methods have been established.

Biodegradable cement augmentation of gamma nail osteosynthesis reduces migration in pertrochanteric fractures, a biomechanical in vitro study.

Background: Cut-out of gamma nail often results from poor primary bone stability, suboptimal reduction (varus) and excentric placement of the head element which may lead to "instability" and frequently requires revision. Various studies have shown that augmentation with polymethylmethacrylate cement increases the primary stability of osteosynthesis. However, it has not yet been widely used in fracture treatment due to certain disadvantages, e.

Reliability analysis of CT torsion assessment after closed cephalomedullary nailing of trochanteric femoral fractures. A comparison study of six established methods.

Background: Posttraumatic maltorsion and implant failure after closed reduction of proximal femoral fractures remain a cause of concern. Although the reproducibility of torsion measuring techniques on CT for femoral shaft fractures has been thoroughly analyzed, little is known about the trochanteric fractures. Apart from the well-known CT limitations, posttraumatic alteration of bony landmarks makes torsional assessment even more challenging.

A novel method for intraoperative osseomechanical strength measurements: a biomechanical ex vivo evaluation on proximal femora.

Introduction: The increasing number of geriatric traumatology cases has intensified the need to reliably and objectively evaluate local bone quality, the latter poses a decisive factor for the choice of an optimal approach to treat osteoporotic fractures. Osteodensitometry imaging techniques are not routinely available in acute operative settings, nor do they provide objective information on local bone properties specifically needed for the prognosis of implant stability.

Materials And Methods: This study sought to verify ex vivo the feasibility and sensitivity of a novel method for the determination of local bone strength in the acute operative setting (intraoperative osseomechanical strength measurement; IOSM) that is based on the principle of material displacement resistance against the force of a rotary indenter.

Anchoring of a Kinked Uncemented Femoral Stem after Preparation with a Straight or a Kinked Reamer.

Objective: To investigate a stem-adjusted preparation of the femur with a kinked reamer and to determine whether this approach results in higher primary stability of a kinked stem than straight reaming of the intramedullary canal.

Methods: Ten cementless stems with a kinked design were implanted in synthetic femurs after preparation of the femoral canal with 2 different reamer designs (straight reaming [SR] group vs kinked reaming [KR] group). The specimens were analyzed using CT to determine the anchoring length and examined with a mechanical testing system to establish their axial stiffness, torsional stiffness, and migration distance after 10 000 gait cycles.

Sagittal profile has a significant impact on the explantability of well-fixed cemented stems in revision knee arthroplasty: a biomechanical comparison study of five established knee implant models.

Background: Easy revisability is gaining increasingly in importance. The removal of well-fixed cemented stems is very demanding and is often associated with increased operative morbidity. Implant design may be here a decisive impact factor, and the best way to ascertain it is experimentally.

Systematic differences of gluteal muscle activation during overground and treadmill walking in healthy older adults.

Guteal muscle activation during walkway and treadmill walking was compared by means of Surface EMG (SEMG). Healthy older adults (50-75 years, n = 54; 29 females, 25 males) walked on a walkway (WW) at their self-selected slow, normal, and fast walking speeds and on a treadmill (TM) at 2, 3, 4, 5, and 6 km/h. Subject-individual, best-matched speed pairs were constituted and named SLOW, NORMAL, and FAST.

Cemented conical stems can be removed more easily than cylindrical stems, regardless of cone angle in revision knee arthroplasty.

Background: According to literature, more than 30% of revised knee arthroplasties will require at least one re-revision. Practical experience has shown that there are considerable product-specific differences in the explantability of cemented long-stem prostheses. In the registers of successful implants, stem geometry varies considerably between the manufacturers.

The Proximal and Distal Femoral Canal Geometry Influences Cementless Stem Anchorage and Revision Hip and Knee Implant Stability.

Although cementless revision arthroplasty of the hip has become the gold standard, revision arthroplasty of the distal femur is controversial. This study evaluated the anchoring principles of different femoral revision stem designs in extended bone defect situations, taking into account the anatomical conditions of the proximal and distal femur, and the resulting primary stability. Cementless press-fit stems of 4 different designs were implanted in synthetic femurs.

Effects on proprioception by Kinesio taping of the knee after anterior cruciate ligament rupture.

Introduction: The use of Kinesio tape (KT) to improve proprioception is a matter of considerable debate. In comparison, the rupture of the anterior cruciate ligament is a sufficiently well-investigated injury with a proven compromise of proprioception. The objective of the present study was to assess a supportive effect on proprioception after KT application, taking the anterior cruciate ligament (ACL) rupture as an example.

The femoral component alignment resulting from spacer block technique is not worse than after intramedullary guided technique in medial unicompartimental knee arthroplasty.

Purpose: Although the spacer block technique has been recommended for the implantation of unicompartmental knee arthroplasty (UKA), there is still a lack of data concerning the resulting component positioning.

Methods: This retrospective study included 193 consecutive patients who had undergone medial UKA using the spacer technique. On the basis of the postoperative long standing radiographs, the coronal component alignment was determined in relation to the mechanical axes and the sagittal component alignment in relation to the anatomical axes of the tibia and femur.

Normalized gait analysis parameters are closely related to patient-reported outcome measures after total knee arthroplasty.

Up till now, only a weak connection could be shown between patient-related outcome measures (PROMs) and measurements obtained by gait analysis (e.g. speed, step length, cadence, ground reaction force, joint moments and ranges of motion) after total knee arthroplasty (TKA).

Anchoring and resulting primary stability of a kinked compared to a straight uncemented femoral stem.

Introduction: The number of revision hip arthroplasties being performed is growing and implantation of a cementless stem has become established as the gold standard. For producing a primary stability, the press-fit procedure is the method of choice, but also can be achieved by multiple-point impactions. Specific femoral stems should follow the anatomical shape and provide a more extensive anchorage.

Patient-Specific Contact Stress Does Not Predict Polyethylene Wear Rate in a Specific Pressfit Cup.

Background: The most common reason for revision total hip arthroplasty remains polyethylene wear. Development dysplasia of the hip and revision situations requires a conscious compromise of implant position. The surgeon should know about the consequence on wear via a possible change in hip contact force.