Cell therapies for chondral defects of the talus: a systematic review.

BACKGROUND: This systematic review investigated the efficacy and safety of surgical procedures augmented with cell therapies for chondral defects of the talus. METHODS: The present systematic review was conducted according to the 2020 PRISMA guidelines. PubMed, Google scholar, Embase, and Scopus databases were accessed in March 2022. All the clinical trials investigating surgical procedures for talar chondral defects augmented with cell therapies were accessed. The outcomes of interest were to investigate whether surgical procedures augmented with cell therapies promoted improvement in patients reported outcomes measures (PROMs) with a tolerable rate of complications. RESULTS: Data from 477 procedures were retrieved. At a mean follow-up of 34.8 ± 9.7 months, the Visual Analogic Scale (VAS) improved of 4.4/10 (P = 0.002) and the American Orthopaedic Foot and Ankle Score (AOFAS) of 31.1/100 (P = 0.0001) points. No improvement was found in Tegner score (P = 0.4). Few articles reported data on complications. At last follow-up, the rate of reoperation and failure were 0.06% and 0.03%, respectively. No graft delamination or hypertrophy was observed. CONCLUSION: The current evidence suggests that cell therapies may be effective and safe to enhance surgical procedures for chondral defects of the talus. These results should be considered within the limitations of the present study. The current literature should be enriched with randomized controlled clinical trials with larger population size and longer follow-up.

A Change in the Classical Order of Setting of Porous Metal Augments with Locked Cups in Hip Revision Surgery: Technical Note and Case Report.

Introduction: Reconstruction of acetabular bone defects by the combination of trabecular metal augments and porous cups can be complex when extensive bone loss and poor-quality bone exists. The onset of porous cups with an interlocking mechanism may simplify surgical technique due to its superior initial mechanical stability. We endorse the possibility for a change in the classical order of setting of the augments and the cup. Methods: We present a technical modification and a series of cases of three patients with Paprosky IIB and IIIA acetabular defects operated with a combination of porous metal augments and a porous cup. In all the three patients, the setting of the cup was done first and secured with locked screws, and then the augments were set in place as a wedge and fixed with screws in a standard fashion. Results: The postoperative X-ray showed good position of implants with restoration of the center of rotation, and the patients had good recovery. Radiological evaluation in the midterm follow-up did not show mobilization of implants. Discussion. The use of metal porous augments is widely used for severe acetabular defects, being a versatile system to adapt to the different size defects. Nevertheless, its use may be technically demanding and time consuming. It is not infrequent that the setting of the augments conditions the final position of the cup with a possible interference with initial stability and eventually bone ingrowth of the cup. The interlocking mechanism offers an additional biomechanical stability and thus may allow us to place the cup first in the desired position with a less demanding technique. Conclusion: With the use of locked-screw porous metal cups, the order of setting of implants may be changed in order to obtain a better restoration of the center of rotation and increased host-bone implant contact with a simplified surgical technique.

Membrane scaffolds for matrix-induced autologous chondrocyte implantation in the knee: a systematic review.

INTRODUCTION: Chondral defects of the knee are common and their management is challenging. SOURCE OF DATA: Current scientific literature published in PubMed, Google scholar, Embase and Scopus. AREAS OF AGREEMENT: Membrane-induced autologous chondrocyte implantation (mACI) has been used to manage chondral defects of the knee. AREAS OF CONTROVERSY: Hyaluronic acid membrane provides better outcomes than a collagenic membrane for mACI in the knee at midterm follow-up is controversial. GROWING POINTS: To investigate whether hyaluronic acid membrane may provide comparable clinical outcomes than collagenic membranes for mACI in focal defects of the knee. AREAS TIMELY FOR DEVELOPING RESEARCH: Hyaluronic acid membrane yields a lower rate of failures and revision surgeries for mACI in the management of focal articular cartilage defects of the knee compared with collagenic scaffolds at midterm follow-up. No difference was found in patient reported outcome measures (PROMs). Further comparative studies are required to validate these results in a clinical setting.

Total hip arthroplasty in patients with severe hip dysplasia and congenital pubic diastasis: report of two cases.

BACKGROUND: Congenital bladder exstrophy is a rare malformation which is often associated with pubic diastasis and hip dysplasia. We reported the case two patients who underwent total hip arthroplasty (THA) due to advanced osteoarthritis combined with large congenital pubic diastasis (> 10 cm). CASE PRESENTATION: The first patient, a 39 years old woman with a pubic diastase and severe hip dysplasia on both sides was treated with a primary two-staged bilateral THA. Both hips were treated with a cementless osteoconductive cup (TM, Zimmer-Biomet) and a cementless stem (Alloclassic SL, Zimmer-Biomet). A 10° elevated rim liner of the cup was used in order to avoid dislocation. The main problem was represented by the fixation of the cup, given the retroverted acetabulum along with the elevated rotation centre due to the dysplastic hips. In the case two, a 52 years woman presented dysplastic osteoarthritis of the left hip. A conventional hemispherical cup (Alloclassic-Allofit, Zimmer-Biomet) was placed in the retroverted acetabulum combined with a cementless stem (Fitmore A, Zimmer-Biomet) attached at the metaphyseal proximal femur bone. CONCLUSION: Our results suggest that THA may be a good strategy to manage advanced hip osteoarthritis in patients with dysplasia and congenital pubic diastasis. LEVEL OF EVIDENCE: IV, case series.

The Rule of Histology in the Diagnosis of Periprosthetic Infection: Specific Granulocyte Counting Methods and New Immunohistologic Staining Techniques may Increase the Diagnostic Value.

OBJECTIVE: The current study investigates the diagnostic accuracy of the criteria described for frozen sections and whether modern leukocyte specific staining techniques including leukocyte peroxidase and Naphtol-AS-D-chloroacetate-esterase will improve the accuracy of the intra-operative histology. METHOD: 77 patients undergoing revision total hip and knee arthroplasty were included in this retrospective study. Patients were grouped into septic and aseptic based on intraoperative cultures. Tissue samples were analyzed utilizing the Mirra, Feldman, Lonner, Banit and Athanasou criteria. RESULTS: An experienced pathologist had a high specificity (96%), but rather low sensitivity (57%) diagnosing infection. By using the Banit-, Mirra-, or Athanasou-criteria the sensitivity is increased to 0.90. The Feldman- and Lonner-criteria have a lower sensitivity (0.48 and 0.38), however, an increased specificity of 0.96 and 0.98, respectively. The Banit cut off has the highest accuracy (86%). MPOX and NACE staining increased the sensitivity and accuracy up to 100% and 92% respectively. CONCLUSION: Banit's cut off is the most accurate histologic criteria to diagnose infection. Modern leukocyte specific staining techniques slightly improve the accuracy. The synovial fluid white blood cell count appears to be the most accurate intraoperative test.

Functional and Emotional Results Differ After Aseptic vs Septic Revision Hip Arthroplasty.

BACKGROUND: It is widely believed that a deep implant infection leads to poor functional and emotional outcomes following total hip arthroplasty. QUESTIONS/PURPOSE: The purpose of this retrospective comparative review was to determine if patients who undergo two-stage, septic revision hip arthroplasty will have decreased emotional and general health scores, in addition to decreased function, compared to the aseptic revision group. PATIENTS AND METHODS: One hundred forty-five of 195 patients who underwent aseptic total hip revision for aseptic loosening (mean follow-up = 61 months) and 45 of 73 patients who underwent two-stage, septic revision hip arthroplasty (mean follow-up = 48 months) met the inclusion criteria and had a technically successful outcome. All patients were retrospectively evaluated using Harris Hip Scores (HHS), ad hoc questions, and the SF-36 Health Survey. RESULTS: The average HHS were 73.2 ± 20.5 (aseptic) and 57.4 ± 20.6 (septic). Significant differences in the SF-36 Health Survey were found between the two groups in: physical functioning (p = 0.026) and role limitations due to physical health (p = 0.004). No significant difference in SF-36 scores was seen in: Energy/Fatigue, General Health Perception, Personal or Emotional Problems, Role Limitations due to Emotional Well Being, Social Functioning, and Bodily Pain. CONCLUSIONS: Two-stage, septic revision produces a poor functional outcome compared to aseptic revision; however, the overall impact of a septic revision emotionally and socially was not significantly different than patients undergoing aseptic revision.

Two-stimuli manipulation of a biological motor.

F1-ATPase is an enzyme acting as a rotary nano-motor. During catalysis subunits of this enzyme complex rotate relative to other parts of the enzyme. Here we demonstrate that the combination of two input stimuli causes stop of motor rotation. Application of either individual stimulus did not significantly influence motor motion. These findings may contribute to the development of logic gates using single biological motor molecules.

The influence of the alloy of megaprostheses on infection rate.

We retrospectively reviewed 197 patients who underwent reconstruction with a megaprosthesis of the lower extremity. A cobalt-chrome alloy system was used in 77 patients and a titanium alloy system in 120 patients. The overall infection rate was 20.8% (n = 41). Separated into the 2 prosthesis systems used, an infection rate of 31.2% was found in the patients with a cobalt-chrome-alloy prosthesis and 14.2% in the titanium alloy group of patients (P < .01). Early infection occurred in 5.1% (n = 10) and late infection in 15.7% (n = 31). Selecting 2 identical subgroups for further analysis, the cobalt-chrome alloy prostheses were associated with a significantly higher infection rate, with 5 infections of 26 megaprostheses vs 1 infection of 36 titanium megaprostheses (P < .05).