Treatment of acute intraoperative Budd-Chiari syndrome by placement of silicone prosthesis

Complete liver mobilization for major resections sometimes causes liver tilting due to the release of the suspensory elements of the liver. Rarely this may take to a liver abnormal position with acute obstruction to venous flow at the suprahepatic level (Budd-Chiari syndrome). To avoid this complication, techniques such as post-operative stent implantation have been described. The case of a patient who underwent a complete mobilization of the liver for resection of the inferior venous cava and a right renal tumor, was reported. After that, an acute Budd-Chiari Syndrome was observed caused of the liver malposition, which was solved with the placement of two silicone prostheses in the liver cell.

Pain, balance, and mobility in people 1 year after total knee arthroplasty: a non-randomized cross-sectional pilot study contrasting posterior-stabilized and medial-pivot designs

BACKGROUND

Total knee arthroplasty (TKA) is a common treatment for severe knee osteoarthritis. Medial-pivot TKA systems (MP-TKA) are theoretically better than posterior-stabilized TKA systems (PS-TKA) in improving static and dynamic balance of patients although it is difficult to objectively quantify these balance parameters in a clinical setting. Therefore, this pilot study aimed to evaluate the feasibility of using wearable devices in a clinical setting to examine whether people with MP-TKA have better postoperative outcomes than PS-TKA, and their balance control is more akin to age-matched asymptomatic controls.

METHODS

The current cross-sectional pilot study recruited 57 participants with 2 different prosthesis designs (20 PS-TKA, 18 MP-TKA) and 19 asymptomatic controls. At 1-year post-TKA, pain, knee stiffness, and physical function were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Static balance, mobility, and gait stability of the participants were evaluated based on data collected from wearable motion sensors during the near tandem stance, timed-up-and-go, and 6-min walk tests.

RESULTS

Compared to asymptomatic controls, both TKA groups reported significantly more pain and stiffness and demonstrated reduced functional mobility, increased stride-time-variability, and impaired balance. After Bonferroni adjustment, no significant differences in pain, balance, and mobility performance were observed between PS-TKA and MP-TKA participants 1 year after surgery. However, there was a trend for increased anteroposterior sway of the lumbar and head regions in the MP-TKA participants when undertaking the near tandem stance test. The wearable motion sensors were easy to use without any adverse effects.

CONCLUSIONS

It is feasible to use wearable motion sensors in a clinical setting to compare balance and mobility performance of patients with different TKA prothesis designs. Since this was a pilot study and no definite conclusions could be drawn, future clinical trials should determine the impacts of different TKA prosthesis designs on post-operative outcomes over a longer follow-up period.

The use of myoelectric prosthesis in a sample of veterans with unilateral upper extremity amputation: prosthesis satisfaction and quality of life

AIMS

To determine the relationship between clinic and prosthesis-related characteristics and psychosocial adjustment, activity restriction, satisfaction with the prosthesis and quality of life in myoelectric prosthesis users with upper limb amputation.

METHODS

Thirty patients with myoelectric prosthesis users with upper limb amputation took part in this study. The patients' demographic and clinical information were recorded. Psychosocial adjustment, activity restriction and satisfaction with the prosthesis were assessed with Trinity Amputation and Prosthesis Experience Scales-Revised (TAPES-R). Short-Form 36 (SF-36) was used for the quality of life.

RESULTS

TAPES-R activity restriction score was significantly higher in patients with transhumeral or elbow disarticulation and with concomitant lower limb amputation (p = 0.009, p = 0.037, respectively). TAPES-R psychosocial adjustment subparameter score had significantly moderate correlation with daily prosthesis wearing time (p = 0.019 r = 0.425). A significant negative correlation was found between age at the time of the injury and SF-36 role limitation due to physical problem (p = 0.028 r = - 0.401).

CONCLUSIONS

Clarifying the factors related to psychosocial adjustment, activity restriction, prosthesis satisfaction and quality of life in individuals with upper extremity amputation and producing interventions/approaches that support patients' life are meaningful and important steps.

CLINICAL TRIAL REGISTER

E2-22-1416.

Demography, Clinical Settings and Outcomes in Evisceration with Implant: An Electronic Medical Records Driven Analytics of 2071 Cases

PURPOSE

To describe the demography, clinical settings and outcomes in 2071 patients undergoing evisceration across a multi-tier ophthalmology hospital network and comparison of results with the global scenario of clinical settings for evisceration.

METHODS

An analysis of 2071 patients undergoing evisceration and implant between 2013 and 2019.

RESULTS

The mean age at surgery was 39 ± 22 years. Children constituted 303(15%) of the cases. The four leading indications for surgery included painful blind eye in 760(37%), phthisis bulbi in 552(27%), staphyloma in 215(10%) and open globe injury in 195(9%) patients. The clinical settings encountered were trauma in 852(41%), ocular infection in 714(34%), glaucoma in 198(10%), post ocular surgery in 146(7%), congenital in 95(5%) and uveitis in 21(1%). Trauma and infection remained the commonest clinical settings in the urban (843,75%), rural (622,77%) and metropolitan (101,71%) areas. Decade wise distribution suggested trauma to be the commonest clinical setting in the first 4 decades and infection in the next 6 decades. The mean follow-up period was 351 ± 386 days (median 194). While trauma remained one of the commonest clinical setting in both the developed and the developing economies, painful blind eye and intractable glaucoma were other common clinical settings in the developed economies and infection was one of the leading clinical setting in the developing economies.

CONCLUSION

Most patients undergoing evisceration are young. The commonest indications for surgery include painful blind eye and phthisis bulbi. Trauma and infection remain the commonest clinical settings for evisceration in developed and developing economies.

Evaluation of Bacteria in a Novel In Vitro Biofilm Model of Penile Prosthesis

BACKGROUND

Delayed infection, thought to be due to gradual biofilm formation, remains a feared complication after inflatable penile prosthesis (IPP) insertion. Understanding and preventing biofilm formation is necessary to prevent infections.

AIM

To develop an in vitro model and compare growth of biofilm by different bacteria on IPPs and evaluate the anti-infective efficacy of the Coloplast Titan and AMS 700 InhibiZone.

METHODS

Sterile IPPs (Coloplast) were cut into rings and incubated with S. epidermidis, S. aureus, P. aeruginosa, A. baumannii, or K. pneumoniae cultures in tryptic soy broth (TSB) (4 hour) to ensure adequate bacteria attachment, and then in only TSB (120 hours) to allow for biofilm formation. Rings were fixed with ethanol and biofilm measured by spectrophotometer (OD570) after crystal violet staining. This methodology was repeated for S. epidermidis and P. aeruginosa with Coloplast rings dipped in 10 ml of a 10 mg/ml Rifampin, 1 mg/ml Gentamicin, and deionized water solution and undipped AMS InhibiZone rings. Crystal violet assay (OD570) was repeated after incubation within bacteria (2 hour), and then only TSB (120 hours).

OUTCOMES

The primary outcome of the study was OD570 readings, indirectly measuring biofilm mass on implant rings.

RESULTS

S. epidermidis, S. aureus, A. baumannii, P. aeruginosa, and K. pneumoniae all formed significant biofilm. P. aeruginosa showed the strongest predilection to grow biofilm on IPPs. P. aeruginosa also formed significant biofilm on antibiotic-treated Coloplast and AMS rings, while S. epidermidis was inhibited. No significant difference was found in biofilm inhibition between the implants.

CLINICAL TRANSLATION

Our findings suggest gram-negative bacteria may form biofilm more proficiently and quickly on IPPs than gram-positive organisms. Commonly used antibiotic treatments on IPPs may be effective against S. epidermidis but not against P. aeruginosa biofilm formation.

STRENGTHS & LIMITATIONS

This is the first study comparing biofilm formation by different bacteria organisms on IPPs and the inhibitive ability of Coloplast and AMS implants against biofilm formation. Clinical data on organisms responsible for infected IPPs is needed to determine the clinical relevance of our findings.

CONCLUSION

Our novel in vitro model of biofilm formation of IPPs evaluated the effect of a gentamicin/rifampin antibiotic dip on Coloplast Titan implants and the anti-infective capacity of the minocycline/rifampin precoated AMS 700 InhibiZone against S. epidermidis and P. aeruginosa. P. aeruginosa was able to grow on both antibiotic-treated implants, with no significant difference, and should continue to be a specific target of investigation to reduce delayed post-operative IPP infections. Narasimman M, Ory J, Bartra SS, et al. Evaluation of Bacteria in a Novel In Vitro Biofilm Model of Penile Prosthesis. J Sex Med 2022;19:1024-1031.

Use of Magnetic Resonance Imaging in women with suspected complications following insertion of implants for pelvic organ prolapse and stress urinary incontinence surgery

OBJECTIVE

To evaluate the role of Magnetic Resonance Imaging (MRI) in women presenting with suspected implant complications following surgery for pelvic organ prolapse (POP) and stress urinary incontinence (SUI).

STUDY DESIGN

Retrospective single-centre cohort study in a designated tertiary referral centre. All women with vaginally and/or abdominally placed implants for POP or SUI who were referred with suspected mesh complications, and investigated with an MRI scan, between January 2018-October 2020 were included in the study.

RESULTS

97 women were identified over this time-period with a total of 123 implants, a median age of 55 years (Range: 34-79) and an average insertion to presentation time of 84 months (Range: 2-300). 78% (74) had one implant in situ, with the remainder having at least 2 in situ. Transobturator tapes (TVT-O/TOT) were the most common implants [35% (43)]. Chronic Pelvic or abdominal pain was the most common clinical symptom [73.2% (71/112 primary complaints)] with provoked tenderness on examination being the most common clinical finding [27.8% (32/115 clinical findings)]. MRI was more likely to detect abdominally placed implants [100% (all 30)] and Retropubic Tapes [89% (16/18)] when compared to Transvaginal POP implants [87.5% (28/32)] and TVT-O/TOT [67% (29/43)]. MRI identified both cases of Sacrocolpopexy mesh rupture as well as all 11 cases of infection (100%). In 91% (10/11) of these cases, MRI revealed the infection to be more widespread than clinical findings initially suspected. Cohen's Kappa demonstrated excellent correlation between MRI and surgical findings in cases with implant related infection, rupture and normal findings (κ = 1; z = 4.58; p = 0.00000459).

CONCLUSION(S)

MRI can be a useful tool in assessment and management of patients with complications from implants. MRI can detect infection that may be more extensive that is initially clinically apparent in the outpatient setting. Abdominal implants appear to be easier to detect than transvaginal meshes and trans obturator tapes.

Powered Knee and Ankle Prosthesis with Adaptive Control Enables Climbing Stairs with Different Stair Heights, Cadences, and Gait Patterns

Powered prostheses can enable individuals with above-knee amputations to ascend stairs step-over-step. To accomplish this task, available stair ascent controllers impose a pre-defined joint impedance behavior or follow a pre-programmed position trajectory. These control approaches have proved successful in the laboratory. However, they are not robust to changes in stair height or cadence, which is essential for real-world ambulation. Here we present an adaptive stair ascent controller that enables individuals with above-knee amputations to climb stairs of varying stair heights at their preferred cadence and with their preferred gait pattern. We found that modulating the prosthesis knee and ankle position as a function of the user's thigh in swing provides toe clearance for varying stair heights. In stance, modulating the torque-angle relationship as a function of the prosthesis knee position at foot contact provides sufficient torque assistance for climbing stairs of different heights. Furthermore, the proposed controller enables individuals to climb stairs at their preferred cadence and gait pattern, such as step-by-step, step-over-step, and two-steps. The proposed adaptive stair controller may improve the robustness of powered prostheses to environmental and human variance, enabling powered prostheses to more easily move from the lab to the real-world.

Psychophysical Evaluation of Proprioceptive Feedback Through a Probe Sliding on the Forearm Skin of Healthy Humans

We have tested the forearm skin of humans as a target organ to deliver proprioceptive feedback via a tactile sensory substitution method. In the proposed method, a contactor probe was actuated by a linear servo motor and moved on the skin in proximo-distal axis depending on the angle of a virtual joint moving on a 180° arc. Twenty healthy subjects were tested to stop the joint at a given target under no-feedback, visual feedback, and tactile (dorsal and volar) feedback conditions. The absolute difference between the target and the response angle was recorded. Tests were repeated 4 times with ~ 1-week intervals. Two joint movement speeds were tested. The subjects performed best with visual feedback, and worst if no feedback was provided. Their performances with tactile feedback were not as good as in the visual feedback condition, but better than in the no-feedback condition. Subjects equally performed with volar and dorsal tactile feedback. The movement speed had no significant effects on tactile feedback. The performance improved with training only in tactile feedback conditions. The proprioceptive information from a motorized prosthesis can be provided through probes moving on the forearm skin, while the efficacy of the feedback may improve with extensive training.

Review of Ischemic and Non-ischemic Priapism

PURPOSE OF REVIEW

Priapism is a rare condition that has different presentations, etiologies, pathophysiology, and treatment algorithms. It can be associated with significant patient distress and sexual dysfunction. We aim to examine the most up-to-date literature and guidelines in the management of this condition.

RECENT FINDINGS

Priapism is a challenging condition to manage for urologists, since the etiology is often multi-factorial and the suggested treatment algorithms are based on small studies and expert anecdotal experience, perhaps due to the rarity of the disorder. Ischemic priapism of less than 24 h can be managed non-surgically in most cases with excellent results. Ischemic priapism of more than 36 h is frequently associated with permanent erectile dysfunction. Management of prolonged priapism with penile shunting still may result in poor erectile function, so penile prosthesis can be discussed in these scenarios.

[Factors related to success in the prosthetic fitting of lower limb amputees from vascular etiology]

OBJECTIVE

Restoring the ambulation ability with prostheses in lower limb amputeesis essential to improve their functional independence. The aim of this study was to determine the factors involved in achieving prosthesis fitting in vascular amputees.

MATERIAL AND METHOD

Observational longitudinal study of patients with major lower limb amputation of vascular etiology performed from April 1st 2017 to April 1st 2020. The following variables were compared between the group of patients who were prosthetized and those who were not: age, gender, body-mass index, comorbidity (Charlson index), independence in the activities of daily living (Barthel index) and ambulation ability (FAC test) before and a year after the amputation. The prosthetic use after a year was measured with the Houghton scale.

RESULTS

A total of 80 patients were amputated with a mean age of 70.5 years old, 78.8% were male. The amputation level was supracondilealin 42 patients and infracondilealin 38 patients. The number of prosthetized patients was 35. The variables related to the possibility of prosthesis fitting were: younger age (P=0.020), less comorbidity (P=0.000), infracondileal amputation (P=0.024) and greater functional independence and ambulation ability prior to amputation (P=0.000). After a year 22 patients had died, only one of those who had been prosthetized.

CONCLUSIONS

Although there are no clear recommendations to determine which amputees should be prosthetic fitting, in our patients the presence of fewer comorbidities and a good previous functional situation, younger age and infracondileal amputation, are related to greater success in achieving this objective.

Factors Associated with Internal Rotation After Reverse Shoulder Arthroplasty: A Narrative Review

Reverse shoulder arthroplasty (RSA) leads to improvement in pain and function with a durable outcome in most cases. While improvement in forward flexion and to a lesser degree external rotation is predictably seen after RSA, restoration of internal rotation (IR) is much less predictable. The purpose of this review was to provide a narrative of the modifiable factors, including prosthetic design and surgical factors, that may impact postoperative IR after RSA. Overall, the available data suggest that postoperative IR is improved with a lower humeral neck shaft angle and lateralization of the glenoid. Decreasing humeral retroversion to 20° or less improves IR at the cost of decreasing active external rotation. Increasing glenosphere diameter improves IR but often within the setting of additional variables. The association between subscapularis repair is less clear but overall suggests that IR is improved postoperatively when it is repaired.

Repair of distal fibular and lateral malleolus defects with individualized 3D-printed titanium alloy prosthesis: The first case report from China

Introduction and importance

This case report describes the reconstruction of the traumatic distal fibular and lateral malleolus defects with a novel method of using individualized 3D printed titanium prosthesis for the first time.

Case presentation

A 63-year-old male farmer was hospitalized in emergency because of open injury and distal fibular and lateral malleolus defects in the left leg caused by a car accident. 3 months after debridement and latissimus dorsi muscle flap transplantation and skin graft operation, the patient re-hospitalized because of distal fibular and lateral malleolus defect and local pain. We examined the bilateral ankle joint with three-dimensional CT, obtained data about the missing left distal fibular and lateral malleolus through the mirror principle. The corresponding titanium alloy prosthesis then was designed and printed using a 3D metal printer. The patient had no obvious contraindication for surgery, so the prosthesis was surgically implanted. The patient was followed up for 2 years. There was no discomfort at the surgical site. The function of the operated ankle was satisfied by the patient, the AOFAS (American Orthopaedic Foot & Ankle Society) score was 85 (Kitaoka et al., 1994 [1]).

Clinical discussion

Individualized 3D printed titanium alloy prosthesis consistent with the anatomical structure of lost distal fibula and lateral malleolus. The proximal end of the prosthesis was designed with four nail holes to install screws to fix the fibula together with it. The lower tibiofibular and talofibular joint surfaces of the prosthesis were designed smoothly. In order to improve the stability of the lower tibiofibular joint, anchors were placed at the attachment of the anterior and posterior tibiofibular ligaments to reconstruct these ligaments.

Conclusion

The structure and function of the reconstructed distal fibular and the lateral malleous were close to normal. Individualized 3D printed prosthesis might have considerable advantages over traditional treatment methods. The individualized 3D printed titanium alloy prosthesis provides a new method for the repair and reconstruction of similar bone defects. The use of 3D printed prosthesis for surgical repair needs to be further examined in the future through long-term follow-up studies and in more cases.

•

Individualized 3D printed prosthesis of traumatic distal fibular and lateral malleolus defects was initially designed.

•

This individualized prosthesis is consistent with the anatomical structure of lost distal fibula and lateral malleolus.

•

The structure and function of the defect site could be reconstructed after prosthesis implantation.

•

Individualized 3D printed titanium alloy prosthesis provides a new method for the reconstruction of similar bone defects.

A Psychosocial Adjustment Measure for Persons With Upper Limb Amputation

BACKGROUND

Measurement of psychosocial adjustment after upper limb amputation (ULA) could be helpful in identifying persons who may benefit from interventions, such as psychotherapy and/or support groups. However, available measures of psychosocial adjustment after limb loss are currently designed for prosthetic users only.

OBJECTIVE

To create a measure of psychosocial adjustment for persons with ULA that could be completed by individuals regardless of whether a prosthesis is use.

METHODOLOGY

We modified items from an existing Trinity Amputation and Prosthesis Experience Survey (TAPES) measure and generated new items pertinent to persons who did not use a prosthesis. Item content was refined through cognitive interviewing and pilot testing. A telephone survey of 727 persons with major ULA (63.6% male, mean age of 54.4) was conducted after pilot-testing. After exploratory and confirmatory factor analyses (EFA and CFA), Rasch analyses were used to evaluate response categories, item fit and differential item functioning (DIF). Item-person maps, score distributions, and person and item reliability were examined. Test-retest reliability was evaluated in a 50-person subsample.

FINDINGS

EFA and CFA indicated a two-factor solution. Rasch analyses resulted in a 7-item Adjustment to Limitation subscale (CFI=0.96, TLI=0.95, RMSEA=0.128) and a 9-item Work and Independence subscale (CFI=0.935, TLI=0.913, RMSEA=0.193). Cronbach alpha and ICC were 0.82 and 0.63 for the Adjustment to Limitation subscale and 0.90 and 0.80 for the Work and Independence subscale, respectively.

CONCLUSIONS

This study developed the Psychosocial Adjustment to Amputation measure, which contains two subscales: 1) Adjustment to Limitation and 2) Work and Independence. The measure has sound structural validity, good person and item reliability, and moderate to good test-retest reliability.

Clinical long-term results of radial head arthroplasty in comminuted radial head fractures

Modern radial head prostheses have recently become more common in the treatment of comminuted radial head fractures. The goal of this study was to evaluate how well the EVOLVE^® modular metallic radial head implant prosthetic restores the functional range of motion and stability of the elbow. 30 patients with comminuted radial head fractures received an arthroplasty with an EVOLVE^® prosthesis in our institution. 20 of those patients were available for long-term follow-up (mean > 10 years). The outcomes were assessed on the basis of pain, motion, and strength. The overall outcome was scored with functional rating scores. According to the Broberg-Morrey elbow evaluation score, after a mean follow-up period of 10.2 years, ten (50.0%) patients were rated as very good, four (20.0%) as good, six (30.0%) as satisfactory, and none as poor. In the long-term results the Broberg-Morrey score increased from 79 (in short-term results) to 89 points. The Disabilities of the Arm, Shoulder, and Hand (DASH) outcome measure questionnaire showed an average of 16.2 points. Initially, patients had an extension deficit of 20°, which was reduced to 5° at the latest follow-up. In our long-term results, an improvement in the function of the elbow was observed after arthroplasty using a metallic modular radial head implant. Comminuted radial head fractures with elbow instability can be treated effectively with the EVOLVE^® radial head prosthesis, which restores stability in acute treatment. Our long-term results after 10.2 years demonstrate good functional outcome and low major complication rate. IV.

Alpha-band activity in parietofrontal cortex predicts future availability of vibrotactile feedback in prosthesis use

Prosthesis disuse and abandonment is an ongoing issue in upper-limb amputation. In addition to lost structural and motor function, amputation also results in decreased task-specific sensory information. One proposed remedy is augmenting somatosensory information using vibrotactile feedback to provide tactile feedback of grasping objects. While the role of frontal and parietal areas in motor tasks is well established, the neural and kinematic effects of this augmented vibrotactile feedback remain in question. In this study, we sought to understand the neurobehavioral effects of providing augmented feedback during a reach-grasp-transport task. Ten persons with sound limbs performed a motor task while wearing a prosthesis simulator with and without vibrotactile feedback. We hypothesized that providing vibrotactile feedback during prosthesis use would increase activity in frontal and parietal areas and improve grasp-related behavior. Results show that anticipation of upcoming vibrotactile feedback may be encoded in motor and parietal areas during the reach-to-grasp phase of the task. While grasp aperture is unaffected by vibrotactile feedback, the availability of vibrotactile feedback does lead to a reduction in velocity during object transport. These results help shed light on how engineered feedback is utilized by prostheses users and provide methodologies for further assessment in advanced prosthetics research.

Dosimetric evaluation of high-Z inhomogeneity used for hip prosthesis: A multi-institutional collaborative study

PURPOSE

A multi-institutional investigation for dosimetric evaluation of high-Z hip prosthetic device in photon beam.

METHODS

A bilateral hip prosthetic case was chosen. An in-house phantom was built to replicate the human pelvis with two different prostheses. Dosimetric parameters: dose to the target and organs at risk (OARs) were compared for the clinical case generated by various treatment planning system (TPS) with varied algorithms. Single beam plans with different TPS for phantom using 6 MV and 15 MV photon beams with and without density correction were compared with measurement.

RESULTS

Wide variations in target and OAR dosimetry were recorded for different TPS. For clinical case ideal PTV coverage was noted for plans generated with Corvus and Prowess TPS only. However, none of the TPS were able to meet plan objective for the bladder. Good correlation was noticed for the measured and the Pinnacle TPS for corrected dose calculation at the interfaces as well as the dose ratio in elsewhere. On comparing measured and calculated dose, the difference across the TPS varied from -20% to 60% for 6 MV and 3% to 50% for the 15 MV, respectively.

CONCLUSION

Most TPS do not provide accurate dosimetry with high-Z prosthesis. It is important to check the TPS under extreme conditions of beams passing through the high-Z region. Metal artifact reduction algorithms may reduce the difference between the measured and calculated dose but still significant differences exist. Further studies are required to validate the calculational accuracy.

Inflammatory myofibroblastic tumor after breast prosthesis: A case report and literature review

BACKGROUND

Inflammatory myofibroblastic tumors (IMTs) are defined as tumors composed of differentiated myofibroblastic spindle cells, usually accompanied by numerous plasma cells and lymphocytes, and classified as intermediate (occasionally metastatic) by the World Health Organization. Its pathogenesis and biological behavior have not yet been elucidated. Breast IMT is extremely rare, and prosthesis implantation combined with IMT has not been reported. This study reports a case of IMT following resection of a malignant phyllodes tumor of the left breast and implantation of a prosthesis.

CASE SUMMARY

A 41-year-old female presented to our hospital with a mass in the left breast for 3 mo. The patient had undergone resection of a large mass in her left breast pathologically diagnosed as a malignant phyllodes tumor and implantation of a prosthesis five years prior. Ultrasonic examination revealed an oval mass in the left breast, and the patient underwent left breast mass resection and prosthesis removal. Light microscopy revealed the spindle cells to be diffusely proliferated, with a large number of neutrophils, lymphocytes, and plasma cell infiltration. Immunohistochemical staining revealed that the spindle cells were partially positive for smooth muscle actin, which is positive for BCL-2 and cluster of differentiation (CD) 99 but were negative for anaplastic lymphoma kinase, cytokeratin, S-100 protein, desmin, and CD34. The final diagnosis was IMT. No recurrence or metastasis was observed during the 5-year postoperative follow-up.

CONCLUSION

Prosthesis implantation may be one of the causes of IMT, but further investigation is necessary to prove it.

Survivorship of the C-Stem total hip replacement using the "French Paradox" technique

BACKGROUND

This study evaluates the survivorship of the C-Stem total hip replacement, using the "French Paradox" method, at medium-term follow-up.

METHODS

321 cemented total hip replacements in 307 patients were performed, using the canal-filling technique for the femoral stem. Survival analysis was performed for all-cause revision. The secondary outcome was aseptic loosening of the stem.

RESULTS

Revision rate for all reasons was 2%. Overall ten-year survival was 95%. There were no revisions for femoral stem aseptic loosening.

CONCLUSION

This is a unique study demonstrating successful outcomes of total hip replacement using the "French Paradox" technique with a triple-tapered stem.

Biomechanical factors affecting individuals with lower limb amputations running using running-specific prostheses: A systematic review

BACKGROUND

Running-specific prostheses (RSPs) are biomechanically designed to enable individuals with lower limb amputations to engage in high level sports.

RESEARCH QUESTION

What is the influence of RSP use on the running biomechanics of individuals with lower limb amputations?

METHODS

An article search was conducted in six databases since their inception to July 2021. Two independent reviewers assessed the title, abstract and full texts in the review process. The quality of the papers was appraised. The review included a total of 35 articles.

RESULTS

Main findings indicate force production is a limitation of RSPs. Individuals with lower limb absence employ a variety of compensatory strategies such as adjusting their step frequency, contact length and joint kinetics to improve their running performance. Leg stiffness modulation and external factors relating to the RSP design and fitting play important roles in RSP biomechanics. For individuals with unilateral amputations, the increased loading of the intact limb could increase the risk of acute injury or chronic joint degradation.

SIGNIFICANCE

To improve their running performance, runners with lower limb amputations employ various compensatory strategies, such as altering the spatiotemporal and kinetic parameters. Factors relating to RSP height, stiffness, shape, and alignment also play an important role in terms of running biomechanics and should be considered in RSP design and fitting. Future studies should focus on the use of RSPs for recreation, in pediatric populations, with certain amputation levels, as well as the impact of training and running techniques.

Experimental measurements of micromotions of the cementless intervertebral disc prostheses in the cadaver bone

BACKGROUND

Sufficient primary stability is mandatory for successful bony prosthetic incorporation. Therefore, defined micromotion values of 150 μm should not be exceeded as higher values might compromise the ingrowth of bone trabeculae to the implant surface. The aim of this study was to evaluate the primary stability of different cementless disc prosthesis in a cadaver model.

METHODS

Four different implants with different anchoring and bearing concept were tested with a target level of L4/5. 26 specimens were randomly allocated to 1 of the 4 different implants with 6 speciments in each group. Two groups were formed depending on the anchoring (spikes vs. fin) and bearing concept (non-/semi- vs. constrained). Each implant was tested regarding primary stability in a hydraulic simulator allowing simultaneous polyaxial segment movements and axial loading. The measurements were recorded on the lower plate of the prosthesis.

FINDINGS

The majority of the implants showed micromotion values below 200 μm in all planes. Only one prosthesis presented borderline longitudinal amplitudes that were significant higher than the other planes. Furthermore, significant differences were observed in the sagittal plane when comparing spike and keel anchoring. Spike anchoring implants showed superior tresults to keel anchoring implants (40 μm vs. 55 μm; p = .039), while the non-/semi-constrained bearing concept was more advantageous compared to constrained group (40 μm vs. 63 μm; p = .001).

INTERPRETATION

Spike anchoring and non-constrained implants might provide better primary stability.

Macrophage Polarization and the Osteoimmunology of Periprosthetic Osteolysis

PURPOSE OF REVIEW

Joint replacement has revolutionized the treatment of end-stage arthritis. We highlight the key role of macrophages in the innate immune system in helping to ensure that the prosthesis-host interface remains biologically robust.

RECENT FINDINGS

Osteoimmunology is of great interest to researchers investigating the fundamental biological and material aspects of joint replacement. Constant communication between cells of the monocyte/macrophage/osteoclast lineage and the mesenchymal stem cell-osteoblast lineage determines whether a durable prosthesis-implant interface is obtained, or whether implant loosening occurs. Tissue and circulating monocytes/macrophages provide local surveillance of stimuli such as the presence of byproducts of wear and can quickly polarize to pro- and anti-inflammatory phenotypes to re-establish tissue homeostasis. When these mechanisms fail, periprosthetic osteolysis results in progressive bone loss and painful failure of mechanical fixation. Immune modulation of the periprosthetic microenvironment is a potential intervention to facilitate long-term durability of prosthetic interfaces.

Mind over matter: Perceived phantom/prosthesis co-location contributes to prosthesis embodiment in lower limb amputees

Prosthesis embodiment - the cognitive integration of a prosthesis into an amputees' body representation - has been identified as important for prosthetic rehabilitation. However, the underlying cognitive mechanisms remain unclear. There is reason to assume that phantom limbs that are experienced as part of the bodily self (phantom self-consciousness) can affect prosthesis embodiment, but only if the phantom and the prosthesis can be brought into perceived co-location (phantom prosthesis tolerance, PPT). In the present study, phantom-prosthesis interactions were examined in lower limb amputees, and a PPT component was psychometrically extracted. Mediation analysis revealed an indirect-only effect, where the relationship between phantom self-consciousness and prosthesis embodiment was mediated by PPT, indicating that phantom limbs can transfer their immanent vividness to the prosthesis. Subsequent analyses suggested that this effect can compensate for negative consequences on prosthesis embodiment that arise from phantom limb awareness. These results shape theoretical considerations about the cognitive processes contributing to the bodily self.

Microbiological pathogen analysis in native versus periprosthetic joint infections: a retrospective study

BACKGROUND

The presence or absence of an implant has a major impact on the type of joint infection therapy. Thus, the aim of this study was the examination of potential differences in the spectrum of pathogens in patients with periprosthetic joint infections (PJI) as compared to patients with native joint infections (NJI).

METHODS

In this retrospective study, we evaluated culture-positive synovial fluid samples of 192 consecutive patients obtained from January 2018 to January 2020 in a tertiary care university hospital. For metrically distributed parameters, Mann-Whitney U was used for comparison between groups. In case of nominal data, crosstabs and Chi-squared tests were implemented.

RESULTS

Overall, 132 patients suffered from periprosthetic joint infections and 60 patients had infections of native joints. The most commonly isolated bacteria were coagulase-negative Staphylococci (CNS, 28%), followed by Staphylococcus aureus (S. aureus, 26.7%), and other bacteria, such as Streptococci (26.3%). We observed a significant dependence between the types of bacteria and the presence of a joint replacement (p < 0.05). Accordingly, detections of CNS occurred 2.5-fold more frequently in prosthetic as compared to native joint infections (33.9% vs. 13.4% p < 0.05). In contrast, S. aureus was observed 3.2-fold more often in NJIs as compared to PJIs (52.2% vs. 16.4%, p < 0.05).

CONCLUSION

The pathogen spectra of periprosthetic and native joint infections differ considerably. However, CNS and S. aureus are the predominant microorganisms in both, PJIs and NJIs, which may guide antimicrobial therapy until microbiologic specification of the causative pathogen.

Risks and Prevention of Surgical Site Infection After Hernia Mesh Repair and the Predictive Utility of ACS-NSQIP

AIM

The aim of this paper was to provide a narrative review of surgical site infection after hernia surgery and the influence of perioperative preventative interventions.

METHODS

The review was based on current national and international guidelines and a literature search.

RESULTS

Mesh infection is a highly morbid complication after hernia surgery, and is associated with hospital re-admission, increased health care costs, re-operation, hernia recurrence, impaired quality of life and plaintiff litigation. The American College of Surgeons National Surgical Quality Improvement Program is a particularly useful resource for the study and evidence-based practise of abdominal wall hernia repair.

DISCUSSION

The three major modifiable patient comorbidities significantly associated with postoperative surgical site infection in hernia surgery are obesity, tobacco smoking and diabetes mellitus. Preoperative optimization includes weight loss, cessation of smoking, and control of diabetes. Intraoperative interventions relate, in particular, to the control of fomite mediated transmission in the operating theatre and prevention of mesh contamination with S. aureus CFUs. Risk management strategies should also target the niche ecological conditions which enable bacterial survival and subsequent biofilm formation on an implanted mesh. Outcomes of mesh infection after hernia surgery are closely related to mesh type and porosity, patient smoking status, presence of MRSA, bacterial adhesion and biofilm production. The use of suction drains and the timing of drain removal are controversial and discussed in detail. Finally, the utility of the ACS-NSQIP Surgical Risk Calculator in predicting complications and outcomes in individual patients and the importance of quality improvement initiatives in surgical units are emphasized.