Validity of Elastic Imaging Evaluation of Hamstring Muscles With Knee Contracture Using Ultrasound Shear Wave Elastography.

PURPOSE: This study used ultrasound shear wave elastography (SWE) to evaluate the mechanical properties of hamstring muscles from cadaveric specimens with knee flexion contractures. METHODS: Hamstring muscles for tensile testing were harvested from Thiel soft-embalmed cadavers with and without knee flexion contracture. Muscle specimens were mounted on a testing machine. The initial load detected when a tensile load was applied to the distal end was used as the slack length. The cross-sectional areas of the muscle at slack length were measured at the proximal and distal sites using B-mode ultrasonography. Subsequently, the muscle specimen was elongated from the slack length to 8% strain, with the shear modulus measured using SWE. Young's modulus (stress/strain) was calculated based on the displacement and tensile force obtained from the tensile test. RESULTS: Regression analysis showed a significant positive linear relationship between the Young's and shear moduli for all specimens at all the sites (P < 0.01 and coefficient of determination: 0.95-0.99). The Young's and average shear moduli at the proximal and distal sites were higher in all hamstring muscles with contractures than in those without contractures. CONCLUSIONS: SWE can be used to estimate Young's moduli of hamstring muscles with contractures. Muscle specimens with contractures exhibited higher resistance to elongation, thereby indicating that their mechanical properties differed from those of muscles without contractures.

Tendon Lengthening Surgery for Elbow Flexion Contractures in Brachial Plexus Birth Palsy.

PURPOSE: Flexion contracture of the elbow is a common deformity associated with brachial plexus birth palsy and is often managed with preventive night orthoses. For severe cases, however, surgical interventions may become necessary. This study evaluated the effectiveness of surgically releasing elbow flexion contractures exceeding 30° through partial tenotomy of the brachialis and biceps brachii muscles, along with a division of the lacertus fibrosus. METHODS: We performed 36 anterior elbow releases on patients with injury to the upper trunk (C5-C6) of the brachial plexus and elbow flexion contractures between 30° and 80°. All releases involved lacertus fibrosus section and partial lengthening of the distal portion of the brachialis tendon. In severe cases, biceps brachii tenotomy was also performed. All participants had a minimum follow-up of 12 months and preoperative elbow flexion strength of at least grade 4 on the British Medical Research Council scale, with no deformities in the shape of the ulnohumeral joint or radial head subluxation. RESULTS: Following a mean follow-up of 41 months, the average extension gain was 31° (range, 10°-50°). All patients maintained their flexion strength. Except for two participants with weaker triceps, the mean elbow extension gain was sustained throughout the follow-up period. There were no major or minor complications or reinterventions in the study. CONCLUSIONS: Partial tenotomy of the brachialis and biceps brachii muscles, coupled with lacertus fibrosus section, is an effective treatment for elbow contractures exceeding 30° flexion. This method is successful in individuals with a functioning triceps brachii and elbow extension strength of at least grade 3 on the British Medical Research Council scale. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Platelet-Rich Plasma as a Novel, Non-invasive Method to Treat Breast Capsular Contractures: a Case Report.

We describe the first examples of breast capsular contracture amelioration using a non-surgical, transdermal treatment with platelet-rich plasma. The treated patients did not experience any complications or significant pain. This report illustrates the potential of a non-invasive treatment option for a common complication of breast augmentation.

Does the timing of anterior cruciate ligament reconstruction surgery affect flexion contracture formation in rats?

BACKGROUND: Anterior cruciate ligament injuries are commonly treated with ligament reconstruction surgery, but post-operative joint contracture is a major complication. The optimal timing for anterior cruciate ligament reconstruction remains controversial, with some clinical studies suggesting that early surgery may increase the risk of joint contractures, while others have found no such association. To clarify this, we investigated the effects of the timing of reconstruction surgery on contracture formation using a rat model. METHODS: Anterior cruciate ligament-transected rats were divided into groups based on the timing of reconstruction: immediate, early, and delayed (1, 14, and 28 days after transection, respectively). Some anterior cruciate ligament-transected rats did not receive reconstruction surgery. Untreated rats served as controls. At 56 days after ligament transection, we assessed knee extension range of motion before (including both myogenic and arthrogenic factors) and after myotomy (arthrogenic factor only), as well as fibrotic changes in the joint capsule. FINDING: Anterior cruciate ligament transection alone significantly decreased range of motion before myotomy, but not after myotomy. In all reconstructed groups, both range of motions before and after myotomy were significantly reduced compared to the control, indicating the induction of arthrogenic contracture by reconstruction surgery. Fibrotic changes in the joint capsule were observed in all reconstructed groups, contributing to arthrogenic contracture formation. However, the timing of reconstruction had no effect on range of motions and fibrotic changes in the joint capsule. INTERPRETATION: Our findings may help guide clinical decision-making regarding the timing of anterior cruciate ligament reconstruction surgery.

Combined awake videolaryngo-bronchoscopy intubation with HFNC preoxygenation for predicted difficult airway in a patient with post-burn mentosternal scar contracture.

Airway management and safety remain a difficult challenge during reconstructive surgery in patients with extensive post-burn mentosternal scar contractures. Current guidelines do not recommend the use of direct laryngoscopy for predicted difficult airway because of the risk of intubation failure and airway emergencies: the consequences of wrong decisions can be fatal, and the patient is at serious risk. At present, video-laryngoscopy is the most commonly used technique for routine orotracheal intubation. Awake tracheal intubation with fibro-bronchoscopy also remains a valid option when possible, ensuring the patient's spontaneous breathing during the procedure. However, when videolaryngoscopy is used in combination with this method, the efficiency of these devices can be increased, and a better result can be achieved. We report a case of successful management of a predicted difficult airway with combined video laryngo-bronchoscopy in an awake patient with post-burn neck scar contractures.

Individual Joint Distractions Using Ilizarov Mini-Fixator Device for Chronic Simultaneous Dislocation of the Distal and Proximal Interphalangeal Joints in the Same Finger.

Simultaneous dislocation of the distal and proximal interphalangeal joints is an uncommon injury. Treating chronic cases proves challenging due to severe contractures affecting both joints and surrounding soft tissues. Here, we report an unusual chronic contracture case in a 46-year-old man who suffered a dorsal dislocation of the distal and proximal interphalangeal joints of the little finger. The patient underwent primary joint distraction followed by open reduction, leading to stable radiographic restoration and a functional range of motion in the affected finger 6 months postoperatively. Joint distraction was a reliable approach for the treatment of chronic joint dislocation with severe soft tissue contracture, especially for multiple joint contractures. In addition, the Ilizarov mini-fixator device was effective in enabling individualized traction on both the distal and proximal interphalangeal joints.

Surgical reconstruction for spasticity and contracture: An underutilised rehabilitative strategy of adult stroke.

Post-stroke spasticity and contracture remain prevalent and pose significant challenges in stroke rehabilitation. While non-surgical management is the mainstay, surgical reconstruction offers a valuable adjunct when conservative measures are exhausted. This clinical review article provides an overview of surgical reconstruction for limb spasticity and contracture following adult stroke, encompassing the rationale and specifics of these interventions. It highlights the underutilization of surgical reconstruction in rehabilitation of adult stroke patients with spasticity and contracture, and the importance of multidisciplinary collaboration including surgeons in stroke rehabilitation to optimize functional outcomes.

Changes in Lower Extremity Passive Range of Motion and Muscle Strength After Selective Percutaneous Myofascial Lengthening and Functional Physiotherapy in Children With Cerebral Palsy.

Background Children with cerebral palsy (CP) often experience motor and postural disorders, along with spasticity, muscle weakness, muscle-tendon contractures, and decreased joint range of motion (ROM). Muscle-tendon contractures are typically addressed through orthopaedic surgery to improve joint ROM, which can result in further muscle weakness. This study aimed to investigate the impact of selective percutaneous myofascial lengthening (SPML) combined with functional physiotherapy on joint passive ROM and isometric muscle strength in the lower extremities of children with spastic CP. Methods A single-group pre- and post-test design was utilised in this study. Twenty-six children aged five to seven years with spastic CP and Gross Motor Function Classification System levels II-IV underwent the SPML procedure and received nine months of postoperative functional strength training physiotherapy. Joint passive ROM and isometric muscle strength were measured using a universal goniometer and a digital hand-held dynamometer, respectively. Paired-sample t-tests were conducted to compare baseline and follow-up measurements. Results Significant improvements (p < 0.05) were observed in passive ROM of hip abduction, straight leg raise, popliteal angle, and ankle dorsiflexion, as well as in isometric strength of hip flexors, extensors, abductors and adductors, knee extensors, and ankle dorsiflexors. Conclusions The SPML procedure supported by postoperative functional physiotherapy can effectively address fixed contractures by significantly increasing passive joint ROM and muscle strength. Further research with longer-term follow-up measurements is necessary to confirm and expand upon these findings.

Fibrotic Contracture of the Infraspinatus Muscle with or without Contracture of the Teres Minor Muscle: A Retrospective Study in Eight Dogs.

(1) Background: Fibrotic contracture of the canine infraspinatus muscle (FCIM) is considered an uncommon musculotendinous condition mainly affecting hunting dogs. After an acute onset of a painful non-weight-bearing lameness over a period of one to four weeks, a characteristic circumducted gait is developed in the affected thoracic limb. (2) Methods: Eight client-owned dogs of varying breeds, both sexes, aged 4-9 years old, and weighing 14-26 kg participated in the study. The duration of lameness prior to their first consultation ranged from 10 to 450 days. All participants were thoroughly examined clinically, orthopedically, and radiographically. (3) Results: The dogs underwent infraspinatus tenotomy, resulting in improved limb function. In three cases, a teres minor muscle contracture was revealed intraoperatively and resolved via a tenotomy at its insertion. The findings showed that 15 days post-operation, all dogs returned to full activity. The results obtained confirm and reinforce the literature data around FCIM and describe the first recorded condition of the simultaneous contracture of the infraspinatus and teres minor muscles. (4) Conclusions: In every case of shoulder lameness, contractures of all shoulder muscles should be included in the differential diagnosis and patients should be assessed for concurrent contractures even if infraspinatus contracture is identified.

Extracorporeal Shock Wave and Melatonin Alleviate Joint Capsule Fibrosis after Knee Trauma in Rats by Regulating Autophagy.

BACKGROUND: Joint contracture is a common clinical problem affecting joint function. Capsule fibrosis plays a pivotal role in the progression of Joint contracture. Previous studies have reported that autophagy plays a regulatory role in visceral fibrosis. OBJECTIVE: This study aimed to investigate whether extracorporeal shock wave therapy (ESWT) and melatonin alleviate joint capsule fibrosis in rats with extended knee joint contracture by regulating autophagy. METHODS: A rat knee joint extension contracture model was made. Then, the rats were treated with ESWT, melatonin, ESWT + melatonin, or ESWT + melatonin + mTOR agonist for 4 weeks. The range of motion (ROM) of the knee joints was measured. Joint capsules were collected and observed for pathological changes by H&E and Masson staining. LC3B protein expression was evaluated by immunofluorescence staining. TGF-ß1, MMP-1, Col-Ⅰ, Col-Ⅲ, LC3, ATG7, Beclin1, p-AMPK, p-mTOR and p-ULK1 protein expressions were measured by Western blot assay. RESULTS: The intervention groups had significantly improved ROM of knee joint (P < 0.05), significantly improved pathological changes on HE and Masson staining, significantly decreased protein expressions of TGF-ß1, MMP-1, Col-Ⅰ, Col-Ⅲ and pmTOR (P < 0.05), and significantly increased protein expressions of LC3B, LC3II/LC3I ratio, ATG7, Beclin1, p-AMPK, and p-ULK1 (P < 0.05). Among these groups, the effects demonstrated by the ESWT + melatonin group were the best. With the mTOR agonist supplement, the therapeutic effects of extracorporeal shock waves and melatonin were significantly reduced. CONCLUSION: ESWT plus melatonin alleviated knee joint capsule fibrosis in rats by regulating autophagy.

Capsular contracture in breast reconstruction: A systematic review and meta-analysis.

BACKGROUND: Capsular contracture after implant-based breast reconstruction is not an uncommon problem and affects reconstruction outcomes. It can be influenced by various factors, such as the plane of implant placement, implant surface and implant type. This systematic review and meta-analysis aimed to evaluate how the abovementioned risk factors can affect capsular contracture rates. METHODS: A systematic review and meta-analysis was performed. PubMed MEDLINE, EMBASE (OvidSP) and Cochrane Library were searched. Comparison groups included subpectoral versus prepectoral implant placement, smooth versus textured implants and saline versus silicone implants. Odds ratios (ORs) were calculated for capsular contracture for each group. The level of evidence was evaluated using the Oxford Centre for Evidence-Based Medicine. RESULTS: Twenty-three studies met the inclusion criteria. Sixteen studies compared subpectoral versus prepectoral implant placement, with no statistically significant differences in capsular contracture rates [OR, 1.21; 95% confidence interval (95% CI), 0.75-1.95; P = 0.44]. Five studies compared smooth versus textured implants, with no statistically significant differences in capsular contracture rates (OR, 0.99; 95% CI, 0.50-1.93; P = 0.97). Two studies compared saline versus silicone implants for capsular contracture. Patients receiving saline implants had significantly lower capsular contracture rates than silicone implants (OR, 0.19; 95% CI, 0.08-0.43; P < 0.0001). CONCLUSIONS: Implant-based breast reconstruction using saline implants demonstrated reduced capsular contracture rates compared to silicone implants. However, no significant differences were observed in capsular contracture rates between subpectoral versus prepectoral implant placement and smooth versus textured implants.

Comparative analysis of length gain provided by five-flap f-flasty and fouble f-plasty fechniques for correction of digital flexion contractures.

INTRODUCTION: Persistent postburn flexion contractions of the digits present challenging deformities. The surgical goal is to lengthen the linear scar band on the flexion surface of a finger through local tissue rearrangement using different z-plasty techniques. This study aimed to analyse the length gain and compare outcomes between 5-flap z-plasty and double serial z-plasty techniques for correcting digital flexion contracture. PATIENTS & METHOD: This retrospective study was conducted from November 2022 to January 2024 on patients who presented with digital flexion contractures caused by volar linear scar contracture and who needed surgical intervention. All patients who underwent correction via the 5-flap z-plasty or double z-plasty technique were categorized into two groups. RESULTS: A total of 12 patients were included in this study. All patients successfully achieved complete release of their digital contracture in both groups. While there was a significant increase in the length of the contracture band and extensor lag angle postoperatively in both groups, the mean increase in band length for patients treated with five-flap Z-plasty was significantly greater than that for patients treated with double z-plasty (63.667±13.125% vs. 41.333±12.1764%, respectively). CONCLUSION: The 5-flap Z-plasty technique could be a more favourable alternative to the frequently used double z-plasty method due to its ability to achieve a superior rate of elongation in the contracture band and restore finger function when treating linear digital flexion contractures.

Protective role of transforming growth factor-Β3 (TGF-Β3) in the formation of radiation-induced capsular contracture around a breast implant: In vivo experimental study.

Postmastectomy radiotherapy causes capsular contracture due to fibroproliferation of the capsular tissue around the implant. In fibrosis, unlike normal wound healing, structural and functional disorders are observed in the tissues caused by excessive/irregular accumulation of extracellular matrix proteins. It has been reported that transforming growth factor-ß3 (TGF-ß3) prevents and reverses fibrosis in various tissues or provides scarless healing with its antifibrotic effect. Additionally, TGF-ß3 has been shown to reduce fibrosis in radiotherapy-induced fibrosis syndrome. However, no study in the literature investigates the effects of exogenously applied TGF-ß3 on capsular contracture in aesthetic or reconstructive breast implant application. TGF-ß3, which has a very short half-life, has low bioavailability with parenteral administration. Within the scope of this study, free TGF-ß3 was loaded into the nanoparticles to increase its low bioavailability and extend its duration of action by providing controlled release. The aim of this study is to investigate the preventive/improving effects of radiation induced capsular contracture using chitosan film formulations containing TGF-ß3 loaded poly(lactic-co-glycolic acid)-b-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles in implant-based breast reconstruction. In the characterization studies of nanoparticles, the particle size and zeta potential of the TGF-ß3-loaded PLGA-b-PEG nanoparticle formulation selected to be used in the treatment group were found to be 123.60 ± 2.09 nm and -34.87 ± 1.42 mV, respectively. The encapsulation efficiency of the formulation was calculated as 99.91 %. A controlled release profile was obtained in in vitro release studies. Chitosan film formulations containing free TGF-ß3 or TGF-ß3-loaded PLGA-b-PEG nanoparticles were used in in vivo studies. In animal studies, rats were randomly distributed into 6 groups (n = 8) as sham, implant, implant + radiotherapy, implant + radiotherapy + chitosan film containing unloaded nanoparticles, implant + radiotherapy + chitosan film containing free TGF-ß3, implant + radiotherapy + chitosan film containing TGF-ß3 loaded nanoparticle. In all study groups, a 2 cm incision was made along the posterior axillary line at the thoracic vertebral level in rats to reach the lateral edge of the latissimus dorsi. The fascial attachment to the chest wall was then bluntly dissected to create a pocket for the implants. In the treatment groups, the wound was closed after films were placed on the outer surface of the implants. After administering prophylactic antibiotics, rats were subjected to irradiation with 10 Gy photon beams targeted to each implant site. Each implant and the surrounding excised tissue were subjected to the necessary procedures for histological (capsule thickness, cell density), immunohistochemical, and biochemical (α-SMA, vimentin, collagen type I and type III, TGF-ß1 and TGF-ß3: expression level/protein level) examinations. It was determined that the levels of TGF-ß1 and TGF-ß3 collagen type III, which decreased as a result of radiotherapy, were brought to the control level with free TGF-ß3 film and TGF-ß3 nanoparticle film formulations. Histological analyses, consistent with biochemical analyses, showed that thick collagen and fibrosis, which increased with radiotherapy, were brought to the control level with free TGF-ß3 film and TGF-ß3 nanoparticle film treatments. In biochemical analyses, the decrease in thick collagen was compatible with the decrease in the collagen type I/type III ratio in the free TGF-ß3 film and TGF-ß3 nanoparticle film groups. Changes in protein expression show that TGF-ß3 loaded nanoparticles are more successful than free TGF-ß3 in wound healing. In line with these results and the literature, it is thought that the balance of TGF-ß1 and TGF-ß3 should be maintained to ensure scarless wound healing with no capsule contracture.

Does the Surgeon's Handedness Affect the Complications Rate in the Inframammary Approach Breast Augmentation?

BACKGROUND: Humans show a preference for left or right handedness in most cases. For this reason, surgeons might find it more difficult to operate on the "nondominant breast", i.e. the breast opposite to the surgeon´s dominant hand (left breast for right-handed surgeons and right breast for left-handed surgeons). The nondominant breast might therefore potentially be prone to a higher complication rate. METHOD: Retrospective data of all consecutive patients who underwent breast augmentations by the first author over the past 15 years was reviewed. In all cases, the entire operation was carried out with the surgeon standing on the right side of the table. All the complications of the right and left breasts were analyzed individually. RESULTS: 1707 patients with a minimum follow-up of six months were reviewed. Mean breast implant volume was 305.6 cc and mean follow-up was 16.12 months. A total of 151 complications were found (8.8%), including rotational deformity, capsular contracture, hematoma, seroma, bottoming out, high riding implant, double bubble deformity, implant rupture and infection. Of these complications, 77 (4.51%) affected the left breast, 48 (2.87%) were found on the right breast and 25 (1.46%) were bilateral. This difference was statistically significant. CONCLUSION: Surgeons´ handedness seem to have an impact on the rate of complications after breast augmentation. As a result of some sort of unease when operating on the nondominant breast, this side might be prone to less precision during the dissection and, consequently, to more complications. Our study found that the rate of complications was higher in the nondominant breast. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Downregulation of interleukin 11 regulates the transforming growth factor-ß/ERK1/2 signaling pathway to inhibit articular capsule fibrosis and alleviate post-traumatic articular capsule contracture.

BACKGROUND: Post-traumatic capsular contracture is a common complication of joint injury and surgery. Post-traumatic capsular contracture is associated with fibrosis characterized by excessive differentiation and proliferation of myofibroblasts and abnormal secretion and accumulation of extracellular matrix. Previous studies have suggested that interleukin 11 (IL11) plays a role in myocardial fibrosis. We thus hypothesized that IL11 may play a fibrotic role during capsular contracture, in order to discover new targets for preventing joint capsule contracture. METHODS: We constructed a post-traumatic contracture model by excessively extending the knee joint and fixing the joint in the flexion position, and a post-traumatic joint capsule contracture model was constructed in the wild-type, IL11-/-, IL11 R -/-, α-SMA-cre-IL11fl/fl, α-SMA-cre-IL11Rfl/fl mouse strain, with wild-type mice without any treatment of the knee joint as the control group. Fibrotic markers and the expression of IL11 and IL11 R in knee joint tissue were detected in each group of mice. The NIH3T3 cell line was used for in vitro analyses. The expression of fibrosis markers, IL11, transforming growth factor-ß, and ERK1/2 were detected by western blot, enzyme-linked immunosorbent assay, and real time quantitative polymerase chain reaction. RESULTS: Inhibition of IL11 inhibited ERK1/2 phosphorylation, reduced the secretion of collagen in the joint capsule, and inhibited the excessive differentiation and proliferation of myofibroblasts in the post-traumatic joint capsule contracture, thus alleviating the joint capsule contracture and obtaining better joint mobility. CONCLUSION: Downregulation of IL11 in traumatic joint capsule contracture inhibits ERK1/2 phosphorylation, thus significantly relieving joint capsule contracture. Our findings indicate the transforming growth factor-ß/IL11/ERK1/2 axis is an important pathway for the differentiation of fibroblasts into myofibroblasts. Anti-IL11 treatment is an effective means to prevent traumatic joint capsule contracture.

Aerobic Training and Ointment Effect on range of motion, von Willebrand factor, vascular endothelial factor and Femoral Artery Hemodynamics in Joint Contracture: A Rat Model.

OBJECTIVE: Using a rat model, we investigated the effect of multidisciplinary rehabilitation, including aerobic training and ointment, on the ROM, vWF, VEGF content, and femoral artery hemodynamics in rats with joint contracture. METHODS: A total of 44 Wistar rats were divided into the normal control group (NC, eight rats) and the experimental group (EG). A joint contracture model was established for the rats in the EG group by an external fixator. After fixator removal, 32 rats are further divided into the MC, SC, RE, and SR groups (n = 8). Before and after the 42 day intervention, the ROM, vWF, VEGF, PS, ED, and RI were measured using X-ray imaging, ELISA, and color Doppler ultrasound, respectively. RESULTS: After fixator removal, ROM for EG group was lower than that of the NC group (p < .01). After the intervention, ROM for the SR, RE, and SC groups was improved. The ROM for the SR group reached a similar value for NC group. vWF and VEGF levels in SR group were lower than in the MC, SC, and RE groups (p < .05), and had a similar value to the NC groups. PS value for SR and RE groups was higher than the MC and SC groups. The RI value for SR group was higher than that of NC and MC groups. CONCLUSION: Multidisciplinary rehabilitation used in this study can treat joint contracture synergistically. It improves the ROM of the joint, reduces the content of vWF and VEGF, and improves the femoral artery hemodynamics.

Treatment of Acquired Deforming Hypertonia with Botulinum Toxin in Older Population: A Retrospective Study.

Acquired deforming hypertonia (ADH) affects the daily care of numerous nursing home residents. The aim of this study was to analyze the practice, aims, and effectiveness of botulinum toxin injections (BTxis) in the treatment of older patients with contractures, an indication for which BTxis are still underused. Data were extracted retrospectively from medical records regarding population, contractures, and injections. A prospective analysis was conducted to evaluate treatment goals set by goal attainment scaling (GAS) at T0 and at T1, to evaluate the therapeutic effects. We also recorded the occurrence of side effects, using a telephone questionnaire. This study included 41 patients older than 70 years who had received one or more BTxis for the first time between January 2018 and December 2021. Most of the older people we included lived in an institution (66%), manifested severe dependence, and presented significant morbi-mortality (37% of the patients died in the year after the last injection). The main objectives of these injections were purely comfort, without any functional goals. The GAS scores suggested effectiveness for comfort GAS scores. No complications were recorded. This study highlights the BTxis potential to address the needs of a larger number of older patients with ADH.

Molecular genetics of Dupuytren's contracture.

Dupuytren's contracture (DC) is a fibroproliferative disorder of the palmar fascia characterised by the digits' flexion contractures and is associated with abnormal build-up of type III collagen. The prevalence of the disease is reported to be highest among Northern European descendants. However, the disease is widespread globally with varying prevalence. DC is a multifactorial disease, having both genetic and environmental factors contributing to the causality of the disease. Over the years, various studies have been conducted to understand the molecular mechanism and genetic aspects of DC but there is a lack of reports on the variants found in the exonic regions. Most reports are backdated making it necessary to re-evaluate the variants to further understand the genetic aetiology of DC. In this review, we first highlight the genetic aspects and previous genetic studies on DC. The report is followed by a discussion on the molecular pathways suggested to be associated with DC and a summary of the genetic variants in the exonic regions found in DC and their connections with the molecular pathways. A total of nine variants were reported originating from six genes comprising three pathways. Most variants reported are involved in the Wnt signalling pathway. Moreover, all variants identified are in European/Caucasian subjects and the variants found in the exonic regions are missense variants. A comparison of these findings with variants from populations of other regions can be conducted to identify the variants with the most occurrence to act as biomarkers or therapeutic targets for DC.

The Effects of Botulinum Toxin Type A on the Biological Behavior of Fibroblasts on Silicone Implants.

BACKGROUND: Capsular contracture is one of the most severe complications following breast augmentation surgery. It has been reported that botulinum toxin Type A (BTX-A) can inhibit capsular contracture, but the exact mechanisms remain unclear. Therefore, this study aims to explore the potential mechanisms behind BTX-A's inhibition of capsular contracture by observing its effects on the biological behavior of fibroblasts and its impact on the TGF-ß/Smad signaling pathway. METHODS: In vitro experiments involved culturing fibroblasts on PDMS surfaces, subsequently treating them with various concentrations of BTX-A. Fibroblast proliferation activity was assessed using the CCK-8 assay, while the migration and cytoskeletal morphology of the fibroblasts were meticulously examined. ELISA was utilized to quantify the expression of fibrosis-related cytokines. Gene and protein expressions related to the TGF-ß/Smad pathway were analyzed through real-time PCR and Western blotting techniques. RESULTS: BTX-A moderately enhanced the early proliferation and migration of fibroblasts on the surface of PDMS silicone sheets and reduced the synthesis of collagen types I and III. Furthermore, under the influence of BTX-A, the expression of TGF-ßR2 and α-SMA in the TGF-ß/Smad pathway was significantly inhibited. CONCLUSIONS: This study demonstrates that BTX-A can inhibit fibroblast differentiation by downregulating the expression of TGF-ßR2, thereby suppressing the TGF-ß/Smad pathway. This suggests a possible mechanism through which BTX-A mitigates capsular contracture. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Free Functional Muscle Transfer-Technical Considerations.

Free functional muscle transfers restore voluntary motion in extremities following the loss of local muscle-tendon units. Surgeons, at various levels of expertise, need to consider several technical aspects when performing this procedure. Successful and consistent outcomes can be attained by applying a combination of basic principles, drawing from techniques developed for successful tendon transfers and microsurgical free tissue transfers. Patient preparation through counseling and intensive rehabilitation is essential to achieve the optimal conditions before the transfer.