Implant Malposition Research Articles

Classification of Breast Implant Malposition.

Implant malposition is a well-recognized complication of prosthetic breast implants. However, to date, no objective classification system has been described. The aim of this study was to perform a prospective trial of an objective and reproducible classification system for implant malposition formulated by analyzing retrospective data from a large cohort of patients with implant malposition. The authors retrospectively analyzed the degree of medial/lateral and inferior/superior implant malposition relative to their optimal position within the breast footprint in a series of 189 breasts (n = 100 patients). An objective classification system for implant malposition was devised and then applied to a prospective cohort of 53 breasts in 28 patients with implant malposition. The degree of malposition in a single or combination of axes was categorized according to the distance (measured in centimeters) from the ideal breast footprint. The classification system incorporated the axis of malposition and distance to generate a treatment decision-making guide. Cases of Grade 1 malposition did not warrant surgical intervention, whereas surgical correction was warranted in all Grade 3 cases. In the combined patient cohort (n = 242 breasts, 128 patients), lateral, inferior, medial, and superior displacement ranged between Grades 1 and 3. There was no interobserver variability in the grades assigned to 9 out of 10 patients in the prospective group. A simple and reproducible classification system for implant malposition has been created that allows surgeons to objectively record the extent of malposition, guides surgical decision-making, and can be used to document the results of any intervention.

Endoscopic Transaxillary Breast Augmentation – a Case Series of 1300 Patients

Abstract Level of Evidence: V – case series Goals/Purpose Breast augmentation is currently one of the most common aesthetic surgical procedures performed in the United States. Transaxillary breast augmentation offers an advantageous hidden scar compared with other options for implant placement. While first described as a blunt and blind approach, endoscopic technique further refined this procedure to offer surgeons complete control and visualization of dissection for precise implant placement. Despite this, breast augmentation is done far more commonly as was initially described over 60 years ago with incisions on the breast that can result in visible scarring. The purpose of this study was to report surgical outcomes on the largest published series to date in a patient cohort of 1389 endoscopic transaxillary breast augmentations. We describe the refinement of this technique and statistical analysis of patient outcomes. Methods/Technique This study included all patients with breast hypoplasia who chose endoscopic transaxillary breast augmentation from 2006 to 2022 by a single surgeon (S.C.). All patients were followed for a minimum of 3 months post procedure. All implants used were smooth, round, silicone gel implants with volumes ranging from 180 to 800cc. Implants were placed in the subfascial or submuscular plane. An incision was marked in the most prominent axillary crease. If there were no creases, an incision was marked at the highest point of the armpit along Langer’s lines. A 30 degree endoscope (Karl Storz, USA) was placed in an endoscopic breast retractor (Karl Storz, USA) and dissection proceeded either in the submuscular plane between the pectoralis major and minor, or in the subfascial plane with an angled suction cautery (Black and Black Surgical, Texas). In the case of subfascial implant placement, the pocket was dissected according to the preoperative markings. With submuscular placement, pocket dissection also followed markings, but the pectoralis muscle was divided with cautery from the level of the areola along the sternal origins of the muscle to completely divide the muscle inferiorly and laterally. The inframammary fold was lowered as necessary by cautery dissection above the level of the pectoralis fascia inferiorly. Glandular scoring was performed with cautery when needed as well. After dissection was completed, saline breast implant sizers were inserted and filled with air to estimate implant size and confirm pocket dissection in the upright position. Adjustments were made to the implant pocket with endoscopic cautery dissection as was necessary. Results/Complications A total of 1389 patients were included in our data analysis for surgeries performed between March 2006 and December 2021. Overall complication rate in our cohort was 6.69%. Malposition of implants was the most common complication at 3.64%. Contracture rate was 1.74%. There was a significant increase noted in hematoma rate in subfascial placement (3.51% increase, p-value<0.05) compared to submuscular and a decrease in implant malposition in the subfascial group (6.58% decrease, p-value<0.05) compared to the submuscular group. These complications were largely managed using endoscopic techniques. There were no significant differences noted between subfascial, subglandular and submuscular pocket placement in asymmetry, contracture and hypertrophy. Conclusion We describe a safe and effective approach to endoscopic transaxillary breast augmentation that has demonstrated long term results compared to the direct vision inframammary technique. The advantages of a hidden scar should be a consideration for surgeons to adopt this technique to improve patient outcomes.

O USO DO O-ARM® OU DA RADIOSCOPIA EM CIRURGIAS DA COLUNA: REVISÃO SISTEMÁTICA COM META-ANÁLISE

ABSTRACT The great advances in using new devices and imaging systems in surgeries aim to reproduce an ideal and safe scenario for the surgeon, the team, and the patient. New systems and devices are constantly available to demonstrate and facilitate intraoperative navigation, thereby reducing errors and avoiding complications for the patient and staff. This study evaluates and compares using the O-arm® system and radioscopy in the freehand technique in spine surgeries. For this, searches were conducted in PubMed and Embase for randomized and non-randomized studies using the O-arm® system and radioscopy in spine surgery. Twenty-four studies were included and compared regarding procedure time, accuracy of implant positioning, effective radiation dose, safety, and efficacy. In one study, the O-arm® group showed a shorter surgical time when compared to the freehand technique (222.5 min. [SD=38.0] vs. 255.2 min. [SD=40.3], p=0.011, respectively). In two studies, the freehand technique resulted in a lower effective radiation dose for patients. In 12 studies, a higher incidence of complications was observed among patients undergoing surgery with the freehand technique. It was concluded that using the O-arm® is associated with a reduction in malposition of implants and more safety for instrumented procedures. Still, no evidence exists that its use can result in less surgical time. Level of Evidence I; Diagnostic Analysis and Studies, Investigation of a Diagnostic Test.

Long-Term Outcomes following Hybrid Breast Reconstruction.

Hybrid breast reconstruction combines free tissue transfer with implant placement. Various mesh products have been successfully used to secure the implant position in these reconstructions. In this study, the authors investigate the impact of mesh type on long-term outcomes following hybrid breast reconstruction. A retrospective analysis of all patients with at least 24 months of follow-up after immediate bilateral prepectoral hybrid breast reconstruction was performed. Univariate and multivariable regression analyses were used to evaluate long-term outcomes and compare breasts reconstructed with polyglactin mesh versus acellular dermal matrix (ADM). Thirty-nine patients (78 breasts) who underwent hybrid breast reconstruction with an average follow-up period of 50.4 months (range, 27 to 73 months) were included in the study. Postoperative complications included hematoma ( n = 2 [2.6%]), mastectomy skin necrosis ( n = 12 [15.4%]), and fat necrosis ( n = 6 [7.7%]). There were no instances of implant infection, implant exposure, or flap failure. Polyglactin mesh and ADM were used in 24 breasts and 54 breasts, respectively. Implant malposition and capsular contracture occurred more frequently in the polyglactin cohort leading to 10 (41.7%) instances of reoperation for implant replacement compared with only 1 (1.9%) in the ADM cohort ( P < 0.001). On multivariable regression analysis, polyglactin mesh was associated with a 36-fold greater probability of requiring implant replacement compared with ADM ( P = 0.006). ADM (versus polyglactin mesh) is associated with lower rates of capsular contracture and implant malposition in the context of hybrid breast reconstruction. Therapeutic, III.

(280) Second Stage Surgery After Ring Flap Metoidioplasty: Technique and Outcomes

Abstract Introduction Metoidioplasty is an option for creation of external male-appearing genitalia in transmasculine individuals. Many individuals report good sensory, functional, and aesthetic outcomes following single-stage metoidioplasty with urethral lengthening and scrotoplasty. However, an average of 12% of patients require a second-stage surgery to improve aesthetic appearance, place testicular implants, address complications, and maximally lengthen the neophallus. These procedures are risky to perform at the time of initial metoidioplasty as this may disrupt the vascular supply to the neoscrotum via the anterior branches of the external pudendal artery. We report outcomes of second-stage ring-flap labial metoidioplasty involving monsplasty, upper labia majora dermatolipectomy, and scrotoplasty with testicular implant insertion. Objective Transmasculine individuals who have had metoidioplasty with rotational advancement labia majora flap and (Ghent style) scrotoplasty often desire monsplasty, upper labia majora tissue resection, and testis implant insertion to optimize aesthetics, reduce dysphoria and improve voiding function. We describe our technique and surgical outcomes with dermatolipectomy of the mons pubis (monsplasty) and upper labia majora with simultaneous testis implant insertion. Methods We retrospectively reviewed the outcomes of ring flap metoidioplasty patients who underwent second stage surgery involving monsplasty and upper labia majora dermatolipectomy, and testis implant insertion. Monsplasty is performed by excising excess skin and adipose tissue to better expose the penis and lift the genitals. Upper labia majora tissue is subsequently resected, followed by development of pockets into each hemiscrotum inferiorly. Silicone carving implants are then individually sized and inserted to serve as testicular prostheses. Results From November 2017 to January 2022, 13 patients underwent second stage metoidioplasty and scrotoplasty with testis implant insertion. Mean follow-up was 22 months. Monsplasty was not desired/necessary in two (15%) patients. Implant malposition occurred in one (7.7%) patient, and one (7.7%) patient was unhappy with the overall aesthetics prompting him to seek a second opinion. To date, no surgical revision was desired nor performed. There were no wound or implant infections, and no scrotal necrosis. Conclusions Monsplasty and upper labia majora dermatolipectomy with simultaneous testis implant insertion is a safe and reliable combination of surgeries after metoidioplasty with Ghent style scrotoplasty. Disclosure No

Risk factors for capsular contracture after breast reconstruction with tissue expanders and silicone implants in nonirradiated patients: A retrospective observational cohort study

Breast reconstruction surgery with tissue expanders and silicone implants is widely performed; however, risk factors for late complications such as capsular contracture have not been fully investigated despite their high prevalence. We investigated the association between expander and implant positions and the development of capsular contracture in patients who underwent breast reconstruction surgery over 10 years previously. In this retrospective observational study, we analyzed 239 patients, among whom 69 (28.9%) had developed capsular contracture of Baker Classification grade II or higher. The position of the expander was classified into six categories based on the inferior margin of the healthy breast. The position of the implant was defined as an upward movement from the position of the expander and was classified into three categories based on the inferior margin of the breast at the time of expander insertion. Using multivariate logistic regression analysis, we assessed whether the misalignment of the expander and silicone implant positions affected capsular contracture development. Both expander and implant positions were significantly different between the groups. The odds ratios, adjusted for confounding variables, were 3.4 and 5.2 for an expander position of 1 and 2 lateral fingers upward, respectively, and 4.8 and 45.4 for a silicone implant position of 2 and 3 lateral fingers upward, respectively. We identified malposition of expanders and silicone implants as risk factors for developing capsular contracture. Correct insertion and adequate dilatation of the expander in the correct position could reduce the risk for capsular contracture.

Better accuracy and implant survival in medial imageless robotic-assisted unicompartmental knee arthroplasty compared to conventional unicompartmental knee arthroplasty: two- to eleven-year follow-up of three hundred fifty-six consecutive knees.

Implant malpositioning, joint line (JL) lowering, and malalignment have been identified as risk factors for implant failure in unicompartmental knee arthroplasty (UKA). The aims of this study were to compare the accuracy of implant positioning in robotic-assisted UKA versus conventional UKA in a large cohort and examine the correlation with implant survival at mid-term follow-up. This retrospective study included 356 medial UKAs from 2011 to 2019. The radiological measurements performed were coronal positioning of tibial implant according to Cartier angle (Δ Cartier), posterior tibial slope (PTS), residual hip-knee-ankle (HKA), and JL restoration. Outliers were defined as follows: post-operative HKA < 175° or > 180°, Δ Cartier > 3° or < - 3°, JL change ≥ 2mm, and PTS < 2° or > 8°. The survival probability was reported at the last follow-up. Out of the 356 knees included, 159 underwent conventional UKA (44.5%) and 197 (55.5%) robotic-assisted UKA. The mean follow-up was 61.3months ± 24.0. Robotic UKA was associated with better accuracy compared to conventional UKA in relation to HKA (67% vs 56%, p = 0.023), JL restoration (70% vs 44%, p < 0.0001), PTS (83% vs 55%, p < 0.0001), and tibial varus restoration (65% vs 55%, p = 0.049). Implant survival in the robotic group was found to be superior at the last follow-up (96.4% versus 87.3% at 9years, p = 0.004). Robotic assistance in patients undergoing medial UKA was associated with better accuracy compared to conventional UKA with respect to tibial implant positioning, post-operative limb alignment, and JL restoration. This was translated in improved survival at mid-term follow-up favouring the robotic group.

Our Experience Using Round Nano-Surface Ergonomix Implants for Breast Reconstruction: A Single-Center Retrospective Study.

Round nano-surface Ergonomix (Motiva, Establishment Labs; Alajuela, Costa Rica) implants were developed to address concerns regarding capsular contracture and textured anatomical breasts implants. The authors describe their early experience with Ergonomix implants in breast reconstruction. The authors retrospectively reviewed the charts of 212 patients (321 breasts) who underwent breast reconstruction employing round nano-surface Ergonomix implants between June 2017 and December 2020. Patients were followed for at least 12 months postoperatively. Demographics, surgical data, and postoperative surgical outcomes were recorded. Postoperative physical well-being and satisfaction with the breasts and implant were evaluated with Breast-Q questionnaires. Of 211 patients, 75.4% had surgery due to cancer, and 24.6% underwent prophylactic surgery. Major complications occurred in 21 breasts (6.5%), of which 20 underwent revision operations. Reconstruction failed in 1 case (0.3%). Eleven breasts (3.4%) had minor complications. Immediate breast reconstruction, irradiated breasts, and smokers had higher rates of complications (P = 0.009, 0.02, 0.022, respectively). Rippling was more common in the pre-pectoral implant plane compared with sub-pectoral reconstruction (9% vs 1.2%, P = 0.001). Capsular contracture rate was 0.9% and occurred only in irradiated breasts. Implant malposition (inferiorly and laterally) occurred in 6.5% of the breasts, with no association between implant malposition and implant plane. Early follow-up demonstrated high patient satisfaction with the implant and breasts, and high scores in terms of patients' physical well-being. Breast reconstruction employing the round nano-surface Ergonomix implant yielded low complication rates and high patient satisfaction. The transition from macro-textured to nano-surface implants has operative implications requiring a learning curve and surgical adjustments.

An Acetabular Fracture with a Series of Complications and Their Solutions: A Notable Case Report

Acetabular fractures are associated with various complications such as neurovascular injuries, post-traumatic arthritis, osteonecrosis of the femoral head, difficulty in arthroplasty, etc. Total Hip Arthroplasty (THA) is one of the most successful surgeries done for post-traumatic arthritis of hip joint. THA itself is associated with numerous complications such as intraoperative haemorrhage, infection, deep vein thrombosis, malpositioning of implants, instability, dislocation, and aseptic loosening. We herein report a case of post-traumatic arthritis of hip following acetabular fracture ten years back, who was operated on with total hip arthroplasty. Various complications were encountered during the management of the patient. The patient developed prosthetic joint infection and was operated with implant removal and antibiotics cement spacer application followed by revision arthroplasty with mega prosthesis, which dislocated following a dashboard injury and had undergone open reduction.

First clinical results of a novel minimally-invasive fusion system for the sacroiliac joint.

Sacroiliac joint (SIJ) painful dysfunction is a common source of low back pain (LBP). Several surgical treatment options for SIJ fusion were described. A promising treatment option with demonstrated clinical improvement is the minimally-invasive SIJ fusion. The aim of this case study was to document the effectiveness and safety of the new SIJ system (Torpedo®) over a period of 6 months after the minimally invasive implantation. Patients with failed conservative treatment of painful SIJ dysfunction were enrolled successively in two centers. The Diagnosis was made by positive response to SIJ-injection with local anesthetic and at least by two positive SIJ provocation tests. The Torpedo® Implant system was used for the implantation. This workpiece made of titanium alloy is characterized by a helical profile geometry (CST: chronical spinal turn) with a hydrophilic surface. The evaluated endpoints LBP and grade of disability were assessed using a 0-10 numerical rating scale (NRS), and Oswestry Disability Index (ODI) preoperatively and at one, three and six months postoperatively. 15 patients (10 female, 5 male; mean age 59 ± 13 years) were operated on one after the other. The pain intensity decreased in all 15 patients. After 6 months, a decrease in the median values of 70% (quartiles 1-3: 65-79%) was calculated. The median values of the Oswestry Disability Index after 6 months were 62% (quartiles 1-3: 53-67) lower than before the operation. Before surgery, 13 patients (87%) were taking opioids for pain management. Six months after the operation, opioids were only needed by 3 patients (20%). Implant malpositioning was not detected on plain radiograph. No surgical site infections or perioperative complications occurred. The clinical improvement in early follow up and the absence of surgery related complications demonstrate a high grade of device-related safety and effectiveness of the treatment with a novel minimally-invasive SIJ fusion system.

87. Sacroiliac joint fusion: review of adverse events and strategies to improve patient safety

87. Sacroiliac joint fusion: review of adverse events and strategies to improve patient safety

A New Technique for Breast Pocket Adjustment: Argon Beam Thermal Capsulorrhaphy.

Summary:Implant malposition remains one of the main complications of aesthetic breast augmentation and alloplastic breast reconstruction with expanders and implants. Many capsulorrhaphy techniques have been described to adjust the breast pocket and correct the malposition. In this study, we tested the efficacy of the argon beam coagulator (ABC) for lateral capsulorrhaphy on breast reconstruction patients at the time of expander replacement with a permanent implant. We also experimentally compared the effects of the ABC and the standard electrocautery on fragments of healthy breast capsule. We noted a 69.5% capsule shrinkage with the ABC versus 46.8% with the standard electrocautery. We concluded that breast capsulorrhaphy using the ABC is a safe and efficient technique for the correction of breast implant malposition in both reconstructive and aesthetic breast surgery.

Indications and timing of revision spine surgery in adults after adolescent surgery for idiopathic scoliosis.

Retrospective case series. To characterize the indications and timing of revision spine surgery in adulthood after adolescent surgery for idiopathic scoliosis. Previous studies have shown that revision usually occurs within 3months or more than 5years after the index operation. It is not clear what the indications for and timeline to revision surgery are in these patients during adulthood. 421 patients with idiopathic scoliosis were seen as adults over a 15-year period. 81 patients who had scoliosis surgery prior to age 18 were identified. This cohort was studied for indications and time from index to revision operation. Their clinical presentation and a description of their revision operation was also documented. Of the 81 patients, 18 (22.2%) had a revision surgery as an adult.Indications for revision in order of prevalence were implant malposition, subjacent segment degeneration and stenosis, pseudoarthrosis, delayed deep wound infection, spondylolisthesis, and symptomatic implants. Revisions were indicated generally within 15years or more than 30years after the initial operation. The timeline for revision spine surgery in idiopathic scoliosis was bimodal, with revisions occurring within 15years or over 30years after the initial operation. Implant malposition and subjacent segment degeneration were the most prevalent indications for adulthood revision. Prognostic-IV.

Etiology and Treatment of Peri-Implant Soft Tissue Dehiscences: A Narrative Review.

Implant soft tissue dehiscences compromise not only the aesthetics of the supported restorations but implant survival in the long run. The aim of this narrative review was to briefly present the causative factors of buccal peri-implant soft tissue dehiscences (PSTDs), how these are classified, and the current therapeutic approaches. Implant malposition and the thin peri-implant phenotype are the two major determinants for the occurrence of PSTDs, but other risk factors have also been identified. The most common surgical procedure for treating PSTDs is the split-thickness coronally advanced flap combined with either a connective tissue graft or acellular dermal matrix materials. However, depending on the class and subtype of the dehiscence, the combination of surgical techniques with modifications in the restoration may further ameliorate the final result. In general, within a five-year follow-up period, most techniques lead to a satisfactory aesthetic result, although full coverage of the implant/abutment surface is not always achievable, especially in more extended lesions.

Revision tibiotalar arthrodesis with posterior iliac autograft after failed arthroplasty: A matched comparative study with primary ankle arthrodeses

IntroductionTibiotalar arthrodeses performed after failed ankle arthroplasties are known to be complex procedures with often disappointing functional outcomes. This study reports the results of a revision technique using a posterior iliac crest autograft. HypothesesWe hypothesized that: (1) revision tibiotalar arthrodeses (RTTAs) had functional outcomes which were similar to those of a reference cohort of primary tibiotalar arthrodeses (TTAs) and that (2) the union rate was satisfactory. Materials and MethodsThis retrospective study compared 16 RTTAs performed for failed arthroplasties that caused pain and a functional disability (4 aseptic loosening, 4 massive progressive periprosthetic cysts, 5 malpositioning of implants, and 3 cases of unexplained mechanical pain) with a series of 16 primary TTAs performed for painful ankle osteoarthritis. The groups were matched at a 1:1 ratio for age, sex, side and body mass index. The preoperative workup included a physical exam, the American Orthopaedic Foot and Ankle Society (AOFAS) score, weight bearing radiographs, CT and SPECT scans. Outcomes were assessed both clinically (AOFAS score) and radiographically (X-rays and scans). The mean duration of the procedure (DP), average length of stay (LOS), fusion and complication rates, and time to union were also compared. ResultsAt the mean follow-up of 30 months (range, 12–88) for the RTTA group and 59 months (range, 23–94) for the TTA group (p=.001), the AOFAS score increased from 27 to 70.8 points (p<.001) and from 29.8 to 76.2 points (p<.001), respectively; values were similar at the last follow-up (p=.442). Both groups had similar fusion (94%) and complication rates (12%). The DP was 196.9±33.6min (range, 179–213) vs. 130±28.4min (range, 118–141) (p<.001) and the LOS was 3.8 days (range, 2–6) vs. 3.9 days (range, 2–6) (p<.445) for both groups (RTTA vs. TTA). ConclusionThis RTTA technique using a posterior iliac crest allograft for filling bone defects was validated by the quality of the functional outcomes obtained. Level of EvidenceIV; Comparative retrospective study.

Implant Malposition in Prepectoral Breast Reconstruction: Experience with Natrelle® Cohesive Implants over 6.5 Years

Implant malposition has been reported to be a common reason for revision surgery after implant-based breast reconstruction (IBR). With the recent increase in the use of smooth implants due to concerns for breast implant-associated anaplastic large-cell lymphoma with textured implants, we compared and reported the rates of malposition in prepectoral IBR and identified risk factors. A retrospective review of patients who underwent prepectoral IBR with Natrelle® (Allergan, Inc., Irvine, CA) implants at our institution between January 2014 and May 2020 was performed. Clinical characteristics, implant types, and the rate of malposition, defined as implant flipping or rotation, were recorded. Univariate and multivariable time-to-event analyses using the Cox proportional-hazards model were performed to identify predictors of malposition. Three hundred seventy-five patients (660 breasts) were included. Four hundred forty-one (66.8%) breasts had smooth round implants whereas 219 (33.2%) had textured anatomical devices. Malposition requiring either a manual correction or surgical intervention occurred in 26 (5.9%) smooth round implants versus 3 (1.4%) textured anatomical. Multivariable analysis showed that having a smooth round implant (aHR: 7.19, 95% CI: [2.04 - 25.4]) and an increase in implant volume (aHR: 1.003, 95% CI: [1.001 - 1.006]) were associated with having a malposition requiring intervention. Among smooth round implants; INSPIRA® Cohesive implants were more likely to result in a malposition requiring intervention (p<0.0001) compared to other smooth round implants. Overall, malposition requiring intervention occurred in 5.9% of smooth round implants and 1.4% of textured anatomical implants. Statistical analysis demonstrates that smooth round implants and an increase in implant volume both are associated with a malposition requiring intervention.

Cemented Patellar Implant Malposition: A Non-Issue for the Painful Total Knee Arthroplasty

BackgroundNon-optimal patellofemoral relationships may influence treatment decisions during revision total knee arthroplasty (TKA). We performed this study to determine whether patellar implant malposition or patellar tilt is associated with inferior patient-reported outcome scores or patient satisfaction after primary TKA. MethodsWe identified 396 TKA patients (439 knees) from an institutional registry who had undergone patellar resurfacing, with preoperative and 6-week postoperative radiographs available, and patient-reported outcome measures (PROMs) completed at least 1 year after surgery (mean 505 days). Preoperative patient demographic characteristics, patient-reported expectations, National Institutes of Health - Patient Reported Outcomes Measurements Instrument Systems global health, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, and University of California Los Angeles activity scores were compared between 60 TKAs performed with non-optimal patellofemoral relationships (36 patellar implant malposition, 24 patellar tilt) and 379 TKAs performed with optimal patellar implant placement. ResultsThere were no differences between the 2 cohorts regarding demographic features, preoperative radiographic disease severity, expectations, and PROMs; or postoperative tibiofemoral component alignment, PROMs, and patient-reported satisfaction (P = .48). Knee Injury and Osteoarthritis Outcome Score for Joint Replacement improved similarly (P = .62) for patients with optimal resurfacing (48.5-77.6 points) and non-optimal resurfacing (47.7-76.6 points). A similar proportion of optimal and suboptimal resurfaced patients reported being satisfied with their TKA (92.7% vs 88.1%, P = .29). ConclusionAlthough suboptimal patellofemoral relationships may prompt treatment considerations during revision TKA, the data obtained from this study do not suggest that patellar implant malposition or patellar tilt independently contribute to postoperative pain, functional limitation, or dissatisfaction. Level of EvidenceThis is a level III, retrospective cohort study.

Polydioxanone Internal Support Matrix: A Rationale for Prophylactic Internal Bra Support in Breast Augmentation.

BackgroundTextured breast implants have been used in aesthetic breast surgery to decrease the rates of implant malposition. A recent analysis of a large-volume single-surgeon experience found statistically similar rates of malposition in smooth vs micro-textured breast implants.ObjectivesProphylactic use of a polydioxanone (PDO) internal support matrix in breast augmentation was hypothesized to prevent scar malposition and increase pocket control.MethodsIn total, 200 patients received silicone gel primary augmentations performed by a single surgeon from January 2018 to December 2020; 84 patients received smooth implants alone; 49 patients received micro-textured implants; and 67 patients received smooth implants plus PDO internal support matrix. All surgeries were performed in the dual plane using an inframammary incision. Implant-related complications and scar malposition were recorded and compared.ResultsNo significant difference in implant-related complication rates was found between shell types (3.57% for smooth devices alone and 2.04% for textured devices [P = 0.62; 95% CI −0.06 to 0.01]). There were zero complications in the smooth plus mesh study arm. A comparison of scar malposition rates between the smooth alone and textured groups revealed no significant difference (15.4% for smooth devices and 8.16% for textured devices [P = 0.23; 95% CI −0.12 to 0.01]). The smooth implant group with the prophylactic placement of PDO mesh had the lowest scar malposition rate of 4.48%, a significant difference compared with the smooth devices alone (P = 0.03; 95% CI −0.21 to −0.01).ConclusionsMicro-textured devices show a trend toward decreased scar malposition, although not significant. Prophylactic use of PDO internal support matrix in silicone gel breast augmentation is safe and has the lowest incidence of scar malposition.Level of Evidence: 3

Risk Factors for Anteroposterior Implant Malposition in Postmastectomy Patients with Cohesive Round Implants

BACKGROUND: Round cohesive implants are increasingly popular due to their ability to maintain shape, higher fill volume, and projection. However, they have also been associated with a higher risk of implant flipping. The current literature on risk factors of anteroposterior implant malposition in patients with two-stage implant-based reconstruction (IBR) is scarce. We identified predisposing factors of implant anteroposterior malposition in postmastectomy patients with prepectoral round, cohesive, smooth implants. METHODS: A retrospective review of patients who underwent postmastectomy two-stage IBR with prepectoral Natrelle Inspira Cohesivity Level 3 implants, from 2013 to 2020 at our institution, was conducted. Inclusion criterion was patients 18 years or older who had a prepectoral tissue expander and prepectoral breast implant. Patients who had prior breast reconstruction or aesthetic surgeries were excluded. RESULTS: A total of 214 implants (84.9% bilateral) in 106 patients were included. The mean age at surgery was 51.1 ± 11.4 years, and the mean body mass index was 27.0 ± 4.8 kg/m2. In total, 22.35% had a history of radiation to the chest wall, and 46.3% had chemotherapy. Of all breasts, 79.4% had prior MX tissue expanders, the median implant volume was 485 cm3 (Q1-3: 385–580), and acellular dermal matrix was placed in 65.4% of breasts. Anteroposterior malposition was reported in 19 (8.9%) breasts, 50% of which underwent surgery to correct the flipping. The mean time to implant flipping was 6.1 months (Q1-3: 3.5–16.8), and the mean follow-up time was 12.2 months (5.0–17.5). On univariate analysis, SCX implants [OR= 3.4 (1.3–8.7), P = 0.01], implant volume > 400 cm3 [OR 8.9 (1.2–68.2), P = 0.011], older age at surgery (OR = 1.1 P = 0.022), and BMI (OR=1.1, P = 0.005) were correlated with a higher risk of anteroposterior malposition. CONCLUSIONS: Use of SCX implants, implants with a volume > 400 cm3, older age at surgery, and high BMI increase the risk of anteroposterior malposition in Natrelle Inspira Cohesivity Level 3 implants. These results can be useful for patient counseling, better surgical planning, and improving clinical practice.

The NLRP3-related inflammasome modulates pain behavior in a rat model of trigeminal neuropathic pain

AimsNod-like receptor family pyrin domain containing 3 (NLRP3) may play an important role in neuropathic pain. Treatment for trigeminal neuropathic pain remains a challenge, as common drugs either do not demonstrate beneficial therapeutic effects or induce intolerance in patients. Main methodsIn a rat model of trigeminal neuropathic pain, pain caused by the malpositioning of dental implants is similar to that experienced by humans. We used masculine Sprague-Dawley rats with inferior alveolar nerve damage as a model to investigate the differential regulation of NLRP3. First, we confirmed the level of NLRP3 in the medullary dorsal horn and variation of pain response behavior after silencing the expression of NLRP3 inflammasome bodies in rats with trigeminal neuropathic pain. Second, under localized anesthesia, we extracted the lower left second molar, implanted a micro-dental implant, and deliberately injured the inferior alveolar nerve. Key findingsAfter nerve damage, the level of NLRP3-related inflammasomes was upregulated in microglia and the expression of a component of the inflammasome gradually increased during postoperative days 3–21. The suppression of adenovirus-shRNA-NLRP3 on postoperative day 1 markedly inhibited the expression of pro-inflammatory cytokines and the activation of the inflammasome and mechanical allodynia. Furthermore, it attenuated cell death in microglia, as evidenced by increased Bcl-2, Bcl-xL, Bax, and Bik expression. SignificanceThe level of NLRP3 in the dorsal horn is a pivotal factor in trigeminal neuropathic pain, and inhibition of the early expression of NLRP3 might serve as a potential therapeutic approach.