scholarly journals Redefining Knee Balance in a Medially Stabilized Prosthesis: An In-Vitro Study

2017 ◽  
Vol 11 (1) ◽  
pp. 1165-1172
Author(s):  
Philippe Van Overschelde ◽  
Vera Pinskerova ◽  
Peter P. Koch ◽  
Christophe Fornasieri ◽  
Sandro Fucentese
Keyword(s):  
Soft Tissue ◽  
Soft Tissues ◽  
In Vitro Study ◽  
Lateral Release ◽  
Soft Tissue Release ◽  
Iliotibial Band ◽  
Soft Tissue Envelope ◽  
Medial Side ◽  
Fresh Frozen

Background: To date, there is still no consensus on what soft tissues must be preserved and what structures can be safely released during total knee arthroplasty (TKA) with a medially stabilized implant. Objective: The aim of this study was to analyze the effect of a progressive selective release of the medial and lateral soft tissues in a knee implanted with a medially stabilized prosthesis. Method: Six cadaveric fresh-frozen full leg specimens were tested. In each case, kinematic pattern and mediolateral laxity were measured in three stages: firstly, prior to implantation; secondly, after the implantation of the trial components, but before any soft tissue release; and thirdly, progressively as soft tissue was released with the trial implant in place. The incremental impact of each selective release on knee balance was then analyzed. Results: In all cases sagittal stability was not affected by the progressive release of the lateral soft tissue envelope. It was possible to perform progressive lateral release provided the anterior one-third of the iliotibial band (ITB) remained intact. Progressive medial release could be performed on the medial side provided the anterior fibers of the superficial medial collateral ligament (sMCL) remained intact. Conclusion: The medially conforming implant remains stable provided the anterior fibers of sMCL and the anterior fibers of the ITB remain intact. The implant’s sagittal stability is mainly dependent on its medial ball-in-socket design.

scholarly journals Accuracy of Percutaneous Lateral Release for Hallux Valgus: An Anatomic Study

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0010
Author(s):  
Lara C. Atwater ◽  
Matthew R. McDonald ◽  
Patrick J. Maloney ◽  
Rebecca A. Cerrato
Keyword(s):  
Soft Tissue ◽  
Minimally Invasive ◽  
Proximal Phalanx ◽  
Lateral Collateral Ligament ◽  
Cutaneous Nerve ◽  
Lateral Release ◽  
Soft Tissue Release ◽  
Percutaneous Technique ◽  
Fresh Frozen ◽  
Bunion Correction

Category: Bunion; Other Introduction/Purpose: Minimally Invasive Chevron and Akin (MICA) surgery is growing in popularity. There are now multiple studies comparing minimally invasive bunion correction to traditional open techniques. Many of these studies include percutaneous lateral soft tissue release using a specific blade, while others use an open technique. To our knowledge, there is no prior study confirming the accuracy of soft tissue release via percutaneous technique. Our objective was to evaluate the precision of the percutaneous release, both the structures released and percent release. Additionally, we identified adjacent nerves potentially at risk with a lateral soft tissue release, measuring their proximity to the incision and if they were damaged. Methods: Sixteen fresh frozen cadaveric foot specimens (8 paired limbs) underwent percutaneous lateral release utilizing a beaver blade under fluoroscopic guidance by two Foot and Ankle Fellowship Faculty who regularly perform the procedure. As described in early MICA technique papers by Redfern and Vernois, the blade was inserted into the plantar plate between the lateral sesamoid and the proximal phalanx. Then the blade was rotated laterally while the hallux was directed into varus. The goal was to release the lateral head of the Flexor Hallucis Brevis (FHB) without violating the Lateral Collateral Ligament (LCL). During our experiment the sesamoids were able to be successfully reduced after each release. The specimens were then dissected to reveal the extent of release of the FHB and LCL. Distance was measured between the blade path and the dorsal digital branch of the deep peroneal nerve, as well as the plantar digital nerve. Results: The FHB was at least partially released in 15/16 specimens. It was completely released in two specimens. 5/16 specimens had greater than 50% but less than 100% release and 8/16 specimens had <50% release. The LCL was completely intact in 8/16 specimens. It was partially released in 8/16 specimens (5 less than 50% released and 3 greater than 50% released). There was no correlation between percent of FHB release and the likelihood of LCL release. The dorsal cutaneous nerve was consistently near the path of the beaver blade, with a median distance of 2mm (range 1-8mm). However, the nerve was never found to be incised or transected. Likewise, the plantar nerve was never injured. Conclusion: This study sought to verify the effectiveness of percutaneous lateral release. We found the FHB to be at least partially released in all but one case, resulting in adequate clinical correction of sesamoid position. Full FHB release may not be necessary to achieve the clinical objective of sesamoid reduction. There was no correlation between percent of FHB release and concomitant release of the LCL, which demonstrates the challenge of an isolated FHB release. The dorsal cutaneous nerve was consistently near the blade path but was never injured, suggesting patients should be counseled regarding the risk. [Table: see text]

scholarly journals Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

Arthroplasty ◽  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Toni Wendler ◽  
Torsten Prietzel ◽  
Robert Möbius ◽  
Jean-Pierre Fischer ◽  
Andreas Roth ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Work Experience ◽  
Soft Tissues ◽  
Force Sensor ◽  
Biomechanical Study ◽  
Measuring System ◽  
Wide Range ◽  
Head Neck

Abstract Background All current total hip arthroplasty (THA) systems are modular in design. Only during the operation femoral head and stem get connected by a Morse taper junction. The junction is realized by hammer blows from the surgeon. Decisive for the junction strength is the maximum force acting once in the direction of the neck axis, which is mainly influenced by the applied impulse and surrounding soft tissues. This leads to large differences in assembly forces between the surgeries. This study aimed to quantify the assembly forces of different surgeons under influence of surrounding soft tissue. Methods First, a measuring system, consisting of a prosthesis and a hammer, was developed. Both components are equipped with a piezoelectric force sensor. Initially, in situ experiments on human cadavers were carried out using this system in order to determine the actual assembly forces and to characterize the influence of human soft tissues. Afterwards, an in vitro model in the form of an artificial femur (Sawbones Europe AB, Malmo, Sweden) with implanted measuring stem embedded in gelatine was developed. The gelatine mixture was chosen in such a way that assembly forces applied to the model corresponded to those in situ. A study involving 31 surgeons was carried out on the aforementioned in vitro model, in which the assembly forces were determined. Results A model was developed, with the influence of human soft tissues being taken into account. The assembly forces measured on the in vitro model were, on average, 2037.2 N ± 724.9 N, ranging from 822.5 N to 3835.2 N. The comparison among the surgeons showed no significant differences in sex (P = 0.09), work experience (P = 0.71) and number of THAs performed per year (P = 0.69). Conclusions All measured assembly forces were below 4 kN, which is recommended in the literature. This could lead to increased corrosion following fretting in the head-neck interface. In addition, there was a very wide range of assembly forces among the surgeons, although other influencing factors such as different implant sizes or materials were not taken into account. To ensure optimal assembly force, the impaction should be standardized, e.g., by using an appropriate surgical instrument.

scholarly journals Thermal and non-thermal effects of capacitive–resistive electric transfer application on different structures of the knee: a cadaveric study

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jacobo Rodríguez-Sanz ◽  
Albert Pérez-Bellmunt ◽  
Carlos López-de-Celis ◽  
Orosia María Lucha-López ◽  
Vanessa González-Rueda ◽  
...  
Keyword(s):  
Low Power ◽  
Electric Current ◽  
Thermal Effects ◽  
Sports Medicine ◽  
Current Flow ◽  
In Vitro Study ◽  
Science Data ◽  
Fresh Frozen ◽  
Inflammatory Processes

AbstractCapacitive–resistive electric transfer therapy is used in physical rehabilitation and sports medicine to treat muscle, bone, ligament and tendon injuries. The purpose is to analyze the temperature change and transmission of electric current in superficial and deep knee tissues when applying different protocols of capacitive–resistive electric transfer therapy. Five fresh frozen cadavers (10 legs) were included in this study. Four interventions (high/low power) were performed for 5 min by a physiotherapist with experience. Dynamic movements were performed to the posterior region of the knee. Capsular, intra-articular and superficial temperature were recorded at 1-min intervals and 5 min after the treatment, using thermocouples placed with ultrasound guidance. The low-power protocols had only slight capsular and intra-capsular thermal effects, but electric current flow was observed. The high-power protocols achieved a greater increase in capsular and intra-articular temperature and a greater current flow than the low-power protocols. The information obtained in this in vitro study could serve as basic science data to hypothesize capsular and intra-articular knee recovery in living subjects. The current flow without increasing the temperature in inflammatory processes and increasing the temperature of the tissues in chronic processes with capacitive–resistive electric transfer therapy could be useful for real patients.

Interdigital vs Transarticular Lateral Release With Scarf Osteotomy

2021 ◽  
pp. 107110072110353
Author(s):  
Florian Hartenbach ◽  
Brigitta Höger ◽  
Karl-Heinz Kristen ◽  
Hans-Jörg Trnka
Keyword(s):  
Soft Tissue ◽  
Hallux Valgus ◽  
Rating Scale ◽  
Lateral Release ◽  
Soft Tissue Release ◽  
Foot And Ankle ◽  
Aofas Score ◽  
Level Of Evidence ◽  
Scarf Osteotomy ◽  
Radiographic Outcomes

Background: We compare the clinical and radiographic outcomes of the interdigital approach vs the medial transarticular approach for lateral release combined with scarf osteotomy. Methods: Seventy-seven feet with moderate to severe hallux valgus underwent scarf osteotomy and lateral soft tissue release, using an interdigital approach (n = 36) vs medial transarticular approach (n = 41). The clinical measurements (range of motion, American Orthopaedic Foot and Ankle Society [AOFAS] score) and radiographic data were evaluated preoperatively and at final follow-up (93-124 months postoperatively). Additionally, the numeric pain rating scale and Foot and Ankle Outcome score [FAOS] were assessed postoperatively. Results: The AOFAS score improved from 60 (q1 = 54, q3 = 70) to 93 (q1 = 85, q3 = 98) in the transarticular group, and from 59 (q1 = 50, q3 = 64) to 95 (q1 = 85, q3 = 100) in the interdigital group. The hallux valgus angle improved from 35.7±6.5 degrees to 15.5±7.6 degrees in the transarticular group, and from 36.0±6.8 degrees to 12.9±13.0 degrees in the interdigital group. The intermetatarsal angle improved from 16.5±2.5 degrees to 6.5±2.7 degrees within the transarticular group and from 17.2±2.5 degrees to 7.3±4.3 degrees in the interdigital group. None of the clinical or radiographic parameters showed any significant differences between the treatment groups. Conclusion: Comparison of outcomes between the interdigital approach and the transarticular approach for lateral soft-tissue release with scarf osteotomy are equally successful. The transarticular approach can thus be considered safe and effective, with the additional benefits of just one scar as opposed to 2. Level of Evidence: Level III, therapeutic.

Soft Tissue Thickness Variations of the Nose: A Radiological Study

2020 ◽  
Vol 40 (7) ◽  
pp. 711-718
Author(s):  
Melekber Çavuş Özkan ◽  
Fatma Yeşil ◽  
İnci Bayramiçli ◽  
Mehmet Bayramiçli
Keyword(s):  
Soft Tissue ◽  
Soft Tissues ◽  
Soft Tissue Coverage ◽  
Limited Information ◽  
Tissue Thickness ◽  
Level Of Evidence ◽  
Age And Gender ◽  
Soft Tissue Envelope ◽  
Soft Tissue Thickness ◽  
And Gender

Abstract Background Soft tissue thickness (STT) is a major factor affecting the outcome in rhinoplasty. However, limited information is found in the literature on the age- and gender-related variations of the nasal STT. Objectives The purpose of this study was to measure STT at various landmarks over the nasal framework and compare the age- and gender-related differences. Methods STT measurements were made at 11 landmarks in 325 patients by employing magnetic resonance imaging. Patients were divided into subgroups to compare the STT differences between female and male and between the age groups as young, middle age, and elderly. Results Soft tissue was thickest at the nasion and thinnest at the rhinion. The soft tissue coverage was significantly thicker in the male population at the supratip, tip, nasal bones, upper lateral cartilages, and alar lobules, whereas it is thicker in females at the rhinion. Average thickness of the soft tissues over the entire nasal framework increases with age except the rhinion. Conclusions The STT is variable over different parts of the osteocartilaginous framework. Gender and age influence the STT. The soft tissue is thicker at the distal half of the nose in male patients, and these areas become gradually thicker with age, whereas the soft tissue over the midvault becomes thinner. Increasing age presents a particular challenge to achieve predictable results in rhinoplasty, and an understanding of the soft tissue envelope allows for improved aesthetic outcome. Level of Evidence 2

Energy-Shunting Hip Padding System Attenuates Femoral Impact Force in a Simulated Fall

1995 ◽  
Vol 117 (4) ◽  
pp. 409-413 ◽  
Author(s):  
S. N. Robinovitch ◽  
W. C. Hayes ◽  
T. A. McMahon
Keyword(s):  
Soft Tissue ◽  
Soft Tissues ◽  
Impact Force ◽  
The Elderly ◽  
Impact Behavior ◽  
Human Female ◽  
Female Pelvis ◽  
The Mean ◽  
The Impact

Recent studies suggest that hip padding systems reduce the incidence of hip fractures during falls. However, no data exist on the force attenuating capacity of hip pads under realistic fall impact conditions, and thus it is difficult to compare the protective merit of various pad designs. Our goal is to design a comfortable hip padding system which reduces femoral impact force in a fall below the mean force required to fracture the elderly cadaveric femur. In pursuit of this objective, we designed and constructed a hip pad testing system consisting of an impact pendulum and surrogate human pelvis. We then developed a hip pad containing a shear-thickening material which allows for shunting of the impact energy away from the femur and into the surrounding soft tissue. Finally, we conducted experiments to assess whether the surrogate pelvis accurately represents the impact behavior of the human female pelvis in a fall, and to determine whether our energy-shunting pad attenuates femoral impact force in a fall more effectively than seven available padding systems. We found the surrogate pelvis accurately represented the human female pelvis in regional variation in soft tissue stiffness, total effective stiffness and damping, and impact force attenuation provided by trochanteric soft tissues. We also found that our padding system attenuated femoral impact force by 65 percent, thereby providing two times the force attenuation of the next best system. Moreover, the energy-shunting pad was the only system capable of lowering femoral impact force well below the mean force required to fracture the elderly femur in a fall loading configuration. These results suggest that the force attenuating potential of hip pads which focus on shunting energy away from the femur is superior to those which rely on absorbing energy in the pad material. While these in-vitro results are encouraging, carefully designed prospective clinical trials will be necessary to determine the efficacy of these approaches to hip fracture prevention.

Effect of Donation Time on Platelet Concentrates and Fresh-Frozen Plasma. An in vitro Study

Vox Sanguinis ◽  
1989 ◽  
Vol 56 (1) ◽  
pp. 21-24 ◽  
Author(s):  
Yang O. Huh ◽  
Benjamin Lichtiger ◽  
Geoffrey G. Giacco ◽  
Vincent F. Guinee ◽  
Benjamin Drewinko
Keyword(s):  
In Vitro Study ◽  
Fresh Frozen Plasma ◽  
Vitro Study ◽  
Platelet Concentrates ◽  
Fresh Frozen ◽  
Frozen Plasma
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