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Orthopaedics & Traumatology, Surgery &... Feb 2016Various treatments for patellofemoral instability have been proposed, such as lowering or medialization of the tibial tubercle, division of the lateral retinaculum,... (Review)
Review
Various treatments for patellofemoral instability have been proposed, such as lowering or medialization of the tibial tubercle, division of the lateral retinaculum, plication of the medial retinaculum, lowering of the vastus medialis, and trochleoplasty. However, it has been difficult to analyze the outcomes of each technique because they are often performed in combination. Recent anatomical and biomechanical studies have shown that the medial patellofemoral ligament (MPFL) is the primary stabilizer of the patella between full extension and 30° flexion. For this reason, reconstructing this ligament is relevant, reinforced by promising early clinical results. MPFL reconstruction techniques differ in the graft used and the fixation method. They will be described here as a function of their fixation method, either into bone or soft tissue. The technical challenges, advantages and disadvantages of these different techniques are reviewed in detail, along with the postoperative rehabilitation protocol. Strict technique is needed to prevent postoperative complications, with flexion contracture due to excessive graft tension being the most common complication. Recurrence of the instability is rare after surgery, proof of the dependable nature of these reconstruction procedures.
Topics: Contracture; Femur; Humans; Joint Instability; Knee Joint; Ligaments, Articular; Patella; Postoperative Complications; Quadriceps Muscle; Range of Motion, Articular; Plastic Surgery Procedures; Recurrence; Tibia
PubMed: 26797001
DOI: 10.1016/j.otsr.2015.06.030 -
Journal of Neuroengineering and... Mar 2023Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength...
BACKGROUND
Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength training, among other uses. However, compliance to NMES-treatment is limited by the use of suboptimal stimulation points which may cause discomfort and less effectivity. Knowledge of where one is most likely to find muscle motor points (MP) could improve NMES comfort and compliance.
AIMS
To anatomically map the MPs of the calf as well as to calculate the probability of finding a MP in different areas of the calf.
MATERIAL AND METHODS
On 30 healthy participants (mean age 37 years) anatomical landmarks on the lower limbs were defined. The location of the four most responsive MPs on respectively the medial and lateral head of gastrocnemius were determined in relation to these anatomical landmarks using a MP search pen and a pre-set MP search program with 3 Hz continuous stimulation (Search range:4.0-17.5 mA). The anatomy of the calves was normalized and subdivided into a matrix of 48 (6 × 8) smaller areas (3 × 3 cm), from upper medial to lower lateral, in order to calculate the probability of finding a MP in one of these areas. The probability of finding a MP was then calculated for each area and presented with a 95% confidence interval.
RESULTS
The MP heatmap displayed a higher concentration of MPs proximally and centrally on the calf. However, there were wide inter-individual differences in the location of the MPs. The highest probability of finding a MP was in area 4, located centrally and medially, and in area 29, located centrolaterally and around the maximum circumference, both with 50% probability (95% CI: 0.31-0.69). The second highest probability of finding MPs was in areas 9, 10, 16, proximally and medially, all with 47% probability (95% CI: 0.28-0.66). These areas 4, 9, 10, 16 and 29 exhibited significantly higher probability of finding motor points than all areas with a mean probability of 27% and lower (p < 0.05) The lateral and distal outskirts exhibited almost zero probability of finding MPs.
CONCLUSIONS
This MP heatmap of the calf could be used to expedite electrode placement and to improve compliance in order to receive consistent and enhanced results of NMES treatments.
Topics: Animals; Cattle; Humans; Adult; Muscles; Lower Extremity; Electrodes; Healthy Volunteers; Individuality
PubMed: 36859293
DOI: 10.1186/s12984-023-01152-5 -
Jornal Vascular Brasileiro Nov 2020Vascular Doppler ultrasound is a noninvasive method that can help in diagnostic and therapeutic planning in case of pedal arterial obstructive disease. The dorsalis... (Review)
Review
Vascular Doppler ultrasound is a noninvasive method that can help in diagnostic and therapeutic planning in case of pedal arterial obstructive disease. The dorsalis pedis artery is the direct continuation of the anterior tibial artery and follows a straight course along the dorsum of the foot, leading medially to the first intermetatarsal space, where it gives off its terminal branches. The posterior tibial artery forks distal to the medial malleolus and gives rise to the lateral plantar and medial plantar arteries. The medial plantar artery has a smaller caliber and runs medially in the sole of the foot, while the lateral plantar artery is of larger caliber, following a lateral course in the plantar region and forming the deep plantar arch, which anastomoses with the dorsalis pedis artery via the deep plantar artery. The arteries of the foot can be assessed noninvasively with Doppler, providing an adequate level of anatomical detail.
PubMed: 34211519
DOI: 10.1590/1677-5449.200068 -
Revista Brasileira de Ortopedia Dec 2021To study the anatomy of the medial coracoclavicular ligament and assess the contribution of the acromioclavicular, coracoclavicular and medial coracoclavicular...
To study the anatomy of the medial coracoclavicular ligament and assess the contribution of the acromioclavicular, coracoclavicular and medial coracoclavicular ligaments to the stability of the acromioclavicular joint. Twenty-six shoulders from 16 fresh cadavers were dissected after placement in dorsal recumbency with a 15-cm cushion between the shoulder blades. An extended deltopectoral approach was performed proximally and medially, followed by plane dissection and ligament identification. The acromioclavicular and coracoclavicular distances were measured using points previously marked with a millimeter caliper. Six of these specimens were submitted to a biomechanical study. The acromioclavicular ligament, the coracoclavicular ligament and the medial coracoclavicular ligament were sectioned sequentially, and a cephalic force of 20 N was applied to the lateral clavicle. The acromioclavicular and coracoclavicular distances were measured in each of the ligament section stages. The right medial coracoclavicular ligament presented, on average, 48.9 mm in length and 18.3 mm in width. On the left side, its mean length was 48.65 mm, with a mean width of 17.3 mm. Acromioclavicular, coracoclavicular and medial coracoclavicular ligament section resulted in a statistically significant increase in the coracoclavicular distance and posterior scapular displacement. The medial coracoclavicular ligament is a true ligamentous structure found in all dissected shoulders. Our results showed that the scapular protraction relaxed the medial coracoclavicular ligament, while scapular retraction tensioned it; in addition, our findings demonstrate that this ligament contributes to the vertical and horizontal stability of the acromioclavicular joint.
PubMed: 34900107
DOI: 10.1055/s-0040-1719088 -
Frontiers in Bioengineering and... 2023Knee OA progression is related to medial knee contact forces, which can be altered by anatomical parameters of tibiofemoral alignment and contact point locations. There...
Medial and lateral knee contact forces during walking, stair ascent and stair descent are more affected by contact locations than tibiofemoral alignment in knee osteoarthritis patients with varus malalignment.
Knee OA progression is related to medial knee contact forces, which can be altered by anatomical parameters of tibiofemoral alignment and contact point locations. There is limited and controversial literature on medial-lateral force distribution and the effect of anatomical parameters, especially in motor activities different from walking. We analyzed the effect of tibiofemoral alignment and contact point locations on knee contact forces, and the medial-lateral force distribution in knee OA subjects with varus malalignment during walking, stair ascending and stair descending. Fifty-one knee OA subjects with varus malalignment underwent weight-bearing radiographs and motion capture during walking, stair ascending and stair descending. We created a set of four musculoskeletal models per subject with increasing level of personalization, and calculated medial and lateral knee contact forces. To analyze the effect of the anatomical parameters, statistically-significant differences in knee contact forces among models were evaluated. Then, to analyze the force distribution, the medial-to-total contact force ratios were calculated from the fully-informed models. In addition, a multiple regression analysis was performed to evaluate correlations between forces and anatomical parameters. The anatomical parameters significantly affected the knee contact forces. However, the contact points decreased medial forces and increased lateral forces and led to more marked variations compared to tibiofemoral alignment, which produced an opposite effect. The forces were less medially-distributed during stair negotiation, with medial-to-total ratios below 50% at force peaks. The anatomical parameters explained 30%-67% of the variability in the knee forces, where the medial contact points were the best predictors of medial contact forces. Including personalized locations of contact points is crucial when analyzing knee contact forces in subjects with varus malalignment, and especially the medial contact points have a major effect on the forces rather than tibiofemoral alignment. Remarkably, the medial-lateral force distribution depends on the motor activity, where stair ascending and descending show increased lateral forces that lead to less medially-distributed loads compared to walking.
PubMed: 37731759
DOI: 10.3389/fbioe.2023.1254661 -
Journal of Orthopaedic Surgery and... Sep 2023This study analyzed the advantages and disadvantages of different procedures for stage IIA progressive collapsing foot deformity (PCFD) through three-dimensional finite...
BACKGROUND
This study analyzed the advantages and disadvantages of different procedures for stage IIA progressive collapsing foot deformity (PCFD) through three-dimensional finite element models.
METHODS
A previous validated stage IIA PCFD FEA model was established consisting of 16 bones, 56 ligaments, 5 muscles and soft tissues. The ligament properties of the spring, deltoid, short plantar and long plantar ligaments, and plantar fascia were attenuated according to a previous publication. Medial column fusion (MCF), medializing calcaneal osteotomy (MCO), lateral column lengthening (LCL), and subtalar joint arthroereisis (SJA) operations were simulated in this model. The indexes of plantar stress distribution, maximum von Mises of the medial and lateral columns, strain of the medial ligaments and plantar fascia that supported the medial longitudinal arch, arch height, talo-first metatarsal angle, calcaneus pitch angle, and talonavicular coverage angle were all compared before and after simulated single-foot weight loading.
RESULTS
The maximum plantar stress of PCFD decreased with MCO and SJA but increased with MCF and LCL. MCF and LCL failed to significantly reduce the stress on the medial column fragments, thereby increasing their stress. Both MCO and SJA relieved medial plantar stress. MCF had no significant effect on stress relief of the medial ligament. MCO, LCL, and SJA were all shown to reduce the pressure on the medial plantar ligament, with LCL having the most obvious effect. All four procedures corrected the arch deformity; however, MCF was not as effective as the other methods. SJA is the best method for restoring arch height and correcting arch deformities. For stage IIA PCFD, isolated MCF failed to reduce pressure on the medial column; however, isolated MCO significantly reduced the pressure on the medial plantar and ligamentous soft tissues while restoring the foot's arch and correcting the hindfoot valgus.
CONCLUSION
SJA with type II sinus tarsi implant effectively transferred pressure from the medial plantar tract to the lateral side and restored the arch. Isolated LCL was not found suitable for stage IIA PCFD.
Topics: Humans; Finite Element Analysis; Foot Deformities; Foot; Ligaments, Articular
PubMed: 37741994
DOI: 10.1186/s13018-023-04216-3 -
Orthopaedics & Traumatology, Surgery &... Feb 2023Good patellar tracking is needed for functionally successful total knee arthroplasty (TKA), and depends on several factors. The aim of the present Instructional Lecture... (Review)
Review
Good patellar tracking is needed for functionally successful total knee arthroplasty (TKA), and depends on several factors. The aim of the present Instructional Lecture is to identify the main factors and how to control them so as to optimize patellar tracking: more or less "patella-friendly" prosthetic trochlea design, requiring precise assessment and choice of model; patellar component design; type of tibial implant; surgical approach and management of peripatellar structures, and any lateral release; distal and posterior femoral bone cuts, determining femorotibial alignment, femoral component rotation and patellar height; tibial implant rotation with respect to the anterior tibial tubercle; patellar cut characteristics in resurfacing. In case of instability or patellar maltracking despite correct implant positioning, there are 2 main surgical techniques: medial patellofemoral ligament reconstruction, and anterior tibial tubercle medialization. To obtain optimal patellar tracking, correction of other factors should be associated: trochlear component design, distal and posterior femoral bone cuts, tibial implant positioning, patellar component shape and positioning, etc.
Topics: Humans; Arthroplasty, Replacement, Knee; Patella; Knee Joint; Femur; Tibia
PubMed: 36302447
DOI: 10.1016/j.otsr.2022.103458