Autologous microfragmented adipose tissue treatment of knee osteoarthritis demonstrates effectiveness in 68% of patients at 4-year follow-up

BACKGROUND

Adipose tissue-derived stem cells are an interesting therapeutic option for early knee osteoarthritis (OA) treatment due to their high plasticity, easiness of harvesting and rapidity of administration. The aim of this study was to evaluate the medium-term effectiveness and safety of Microfragmented Autologous Fat Tissue (MFAT) injection treatment at 4-year follow-up and to investigate potential correlations among patients' pre-treatment clinical condition and clinical outcomes to identify possible predicting factors for procedure success or failure.

PATIENTS AND METHODS

This is a prospective trial enrolling 46 patients with diagnosis of symptomatic knee OA and failure of previous conservative measures who underwent diagnostic arthroscopy and single autologous MFAT injection between June 2017 and July 2018. Patients were assessed with repeated clinical scoring systems at baseline, 6 months, 1 and 4 years after surgery. The evaluation included demographic characteristics, arthroscopic findings, and stem cell number from injected tissue.

RESULTS

No major complications were reported during follow-up period and there was a significant increase of Lysholm knee score from baseline value of 61.7 ± 13.8 to 79.5 ± 16.9 at 4 years (p < 0.001). The WOMAC score increased from a baseline value of 66.5 ± 14.7 to 82.8 ± 15.7 at 4 years (p < 0.001) and there was a significant decrease of VAS pain score from baseline value of 6.3 ± 1.5 to 3.5 ± 2.6 at 4-year follow-up (p < 0.001). ROM improved significantly from 118.4 ± 2.6 to 122.5 ± 2.5 at 12 months (p < 0.001), but did not improve at 4 years (p > 0.05). 15 patients (32.6%) were considered treatment failures, because they required secondary surgery, further injection therapy or experienced symptoms persistence. Patient with synovitis had 75% failure rate, although synovitis did not result as a statistically significant factor influencing clinical outcome up to 4-year follow-up (p = 0.058). Age, cartilage defects severity, BMI, concomitant procedures, and stem cell number from injected MFAT did not show any significant correlation with the results.

CONCLUSIONS

MFAT intra-articular injection is a safe procedure with positive improvements up to 4-year follow-up in patients with early knee OA. These findings suggest MFAT could be a minimally invasive treatment of early knee OA with durable benefits at mid-term evaluation.

TRIAL REGISTRATION

IRB number ID-3522.

Age and synovitis affect the results of the treatment of knee osteoarthritis with Microfragmented Autologous Fat Tissue

PURPOSE

This study aims to assess the effectiveness of Microfragmented Autologous Fat Tissue (MFAT) treatment for knee osteoarthritis and to investigate whether patients' pre-treatment clinical condition, such as synovitis, correlates with clinical outcomes, to identify potential predicting factors for the success or failure of the treatment.

METHODS

In this prospective Cohort Study Level II multicentric trial, consecutive patients with a diagnosis of early/mild osteoarthritis and failure of previous conservative measures were enrolled to undergo diagnostic arthroscopy and a single MFAT injection. Patients were assessed with repeated scoring systems at baseline, 6 months, and 12 months after surgery. The demographic features, the arthroscopic findings, the immunophenotype of injected tissue and the histologic examination of synovia of failed patients were analyzed.

RESULTS

Data from 91 patients showed a significant improvement in Lysholm, WOMAC scores at 1-year follow-up (p < 0.001). A significant decrease in VAS score was observed, while a significant improvement of measured flexion angle was registered at 1 year (p < 0.001). No major complications were reported. Age and synovitis were identified as significant factors influencing the clinical outcome (p < 0.05). Body mass index, previous or concomitant procedures, and specific cartilage defects had no influence. The mean number of injected adipose tissue-derived mesenchymal stem cells seem not to correlate with the clinical outcome.

CONCLUSION

MFAT is effective in reducing pain when used with a single dose injection in early/mild OA of the knee, without major complications. Age over 60 and synovitis may be predictive for persistent pain at one year and should be considered before indications.

European Database of Explanted UHMWPE Liners from Total Joint Replacements: Correlations among Polymer Modifications, Structure, Oxidation, Mechanical Properties and Lifetime In Vivo

This contribution lays the foundation for the European database of explanted UHMWPE liners from total joint replacements. Three EU countries (Czech Republic, Italy and Spain) have joined their datasets containing anonymized patient data (such as age and BMI), manufacturer data (such as information on UHMWPE crosslinking, thermal treatment and sterilization), orthopedic evaluation (such as total duration of the implant in vivo and reasons for its revision) and material characterization (such as oxidative degradation and micromechanical properties). The joined database contains more than 500 entries, exhibiting gradual growth, and it is beginning to show interesting trends, which are discussed in our contribution, including (i) strong correlations between UHMWPE oxidative degradation, degree of crystallinity and microhardness; (ii) statistically significant differences between UHMWPE liners with different types of sterilization; (iii) realistic correlations between the extent of oxidative degradation and the observed reasons for total joint replacement failures. Our final objective and task for the future is to continuously expand the database, involving researchers from other European countries, in order to create a robust tool that will contribute to the better understanding of structure-properties-performance relationships in the field of arthroplasty implants.

Highly cross-linked polyethylene versus conventional polyethylene in primary total knee arthroplasty: comparable clinical and radiological results at a 10-year follow-up

PURPOSE

Highly crosslinked polyethylene (HXLPE) was introduced in total knee arthroplasty (TKA) to reduce wear and consequent revisions for loosening due to conventional polyethylene (CPE) wear. This study aims to analyse whether HXLPE is as safe as CPE and could improve the TKA clinical and radiological results in a long-term follow-up.

METHODS

This retrospective study included all consecutive starting series of 223 patients with severe primary knee osteoarthritis (OA), with a minimum follow-up of 10 years treated between July 1st, 2007, and July 31st, 2010. After excluding patients who did not respect the inclusion and exclusion criteria, 128 patients were included in the analysis of this study. The patients were then divided into two groups according to the type of polyethylene (PE) implanted: CPE or HXLPE liners. All patients were evaluated for clinical and radiological parameters, causes and revision rates related to the type of PE implanted.

RESULTS

HXLPE appears to be as safe as CPE in TKA, reporting no higher revisions for osteolysis, prosthesis loosening, infection, and mechanical failure. Nevertheless, no statistically significant differences were found between the two groups in the clinical and radiological outcomes evaluated.

CONCLUSIONS

Clinical, radiological results, and revision rates are similar between HXLPE and CPE in TKA after 10 years of follow-up, although HXLPE benefits remain controversial.

LEVEL OF EVIDENCE

III.

Microfragmented Adipose Tissue (M-FATS) for Improved Healing of Surgically Repaired Achilles Tendon Tears: A Preliminary Study

INTRODUCTION

Tendon healing is a complicated process that results in inferior structural and functional properties when compared with healthy tendon; the purpose of this study was to assess the effects of the adjunct of microfragmented adipose tissue (M-FATS) after the suture of a series of Achilles tendons.

METHODS

After complete Achilles tendon tear, 8 patients underwent open suture repair in conjunction with perilesional application of a preparation of M-FATS rich in mesenchymal stem cells. Results were compared with a similar group of patients treated with conventional open suture. Outcomes were evaluated based on range of motion, functional recovery, and complications according to the American Orthopedic Foot and Ankle Society (AOFAS) score and Foot and Ankle Disability Index (FADI). Achilles tendons were examined by ultrasound (US) at 3 months.

RESULTS

The AOFAS and FADI scores showed no differences between the 2 groups. US evaluation showed quicker tendon remodeling in the M-FATS group. Adverse events were not documented for both procedures.

CONCLUSIONS

The combined application of derived M-FATS for tendon rupture is safe and presents new possibilities for enhanced healing.

LEVELS OF EVIDENCE

Level IIIb: Case control study.

Comparable results between crosslinked polyethylene and conventional ultra-high molecular weight polyethylene implanted in total knee arthroplasty: systematic review and meta-analysis of randomised clinical trials

PURPOSE

Total knee arthroplasty (TKA) has experienced exponential growth over the last decade, including increasingly younger patients with high functional demands. Highly crosslinked polyethylene (HXLPE) has been proven effective in reducing osteolysis and loosening revisions while improving long-term survival and performance in total hip arthroplasty; nevertheless, this superiority is not demonstrated in TKA. The aim of this systematic review and meta-analysis was to examine whether HXLPE improved overall survival and postoperative functional and radiological outcomes compared to conventional polyethylene (CPE) in TKA.

METHODS

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, a literature search of five databases (PubMed, Medline, Scopus, Science Direct and Embase) was made. A PICOS model was performed. The initial screening identified 2541 studies. Each eligible clinical article was analysed according to the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence (LoE). Only randomised clinical trials (RCTs) of LoE 1 and 2 were included. The methodological quality of the articles was assessed using the Risk of Bias 2 (RoB 2) tool.

RESULTS

Six clinical studies were included in the final study. This systematic review and meta-analysis were registered on the International Prospective Register of Systematic Reviews (PROSPERO). A total of 2285 knees were included. Eight outcomes (total reoperations, reoperations for prosthesis loosening and infections, radiolucent lines, osteolysis, mechanical failure, postoperative KSS knee score and function score) were analysed. For none of them, a statistically significant difference was found about the superiority of HXLPE over CPE (p > 0.05).

CONCLUSIONS

There were no statistically significant differences between HXLPE and CPE for TKA concerning clinical, radiological, and functional outcomes; nevertheless, HXLPE did not show higher failure rates or complications and can be safely used for TKA.

LEVEL OF EVIDENCE

II.

Bicruciate-retaining total knee arthroplasty: What’s new?

Primary total knee arthroplasty (TKA) is a widespread procedure to address end stage osteoarthritis with good results, clinical outcomes, and long-term survivorship. Although it is frequently performed in elderly, an increased demand in young and active people is expected in the next years. However, a considerable dissatisfaction rate has been reported by highly demanding patients due to the intrinsic limitations provided by the TKA. Bicruciate-retaining (BCR) TKA was developed to mimic knee biomechanics, through anterior cruciate ligament preservation. First-generation BCR TKA has not gained popularity due to its being a challenging technique and having poor survival outcomes. Thanks to implant design improvement and surgeon-friendly instrumentation, second-generation BCR TKA has seen renewed interest. This review will focus on surgical indications, kinematical basis, clinical results and latest developments of second-generation BCR TKA.

Rehabilitation Protocol After Hip Arthroscopy: A 2015-2020 Systematic Review

OBJECTIVE

Although many rehabilitation protocols after hip arthroscopy have been described, there is still significant variability about duration, goals, restrictions, and techniques to apply by the physical therapy after the surgical procedure. The aim of the study was to systematically review rehabilitation after hip arthroscopy.

DESIGN

The data sources were PubMed, Scopus, and Cochrane Library. The Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were used for the systematic review. Level I-IV evidence clinical studies and clinical reviews that focused on rehabilitation protocols after hip arthroscopy have been used as study eligibility criteria. Major limitations include the retrospective nature of most of the studies selected (level IV evidence) and the use of different clinical scores to report the outcomes.

RESULTS

This review showed that although a standardized guideline on rehabilitation after hip arthroscopy is still missing, the most recent studies and clinical trials are focusing on a four-phase program, which includes goals, recommendations, and a progression of exercises.

CONCLUSIONS

Rehabilitation after hip arthroscopy is strongly suggested, but different authors recommended different rehabilitation programs. There is not a defined program, but as of today, the current standard of care is composed of phase-based programs.

Ultra-high molecular weight polyethylene (UHMWPE) for hip and knee arthroplasty: The present and the future

PURPOSE

to review advances and clinical performance of polyethylene in total joint arthroplasty, summing up historical problems and focusing on the latest innovations.

METHODS

search for medical grade Ultra-High-Molecular-Weight-Polyethylene (UHMWPE); Data Sources: PubMed, Scopus, Cochrane Library.

RESULTS

the increasing number of joint arthroplasties and high-activity patients led to progressive developments of bearing surfaces to improve performance and durability. Different strategies such as crosslinking UHMWPE (HXLPE) and the addition of vitamin-E (HXLPE) have been tested to improve wear and oxidation resistance.

CONCLUSION

Recent innovations about UHMWPE showed improvements either for hip and knee, with the potential of long-term survivorship.

Primary total knee arthroplasty in tibial plateau fractures: Literature review and our institutional experience

BACKGROUND

Displaced proximal tibia fractures in the elderly may be very difficult to manage. If osteosynthesis represents the standard of care in the younger patients, in the aged population this solution is controversial because a significant failure rate has been reported after internal fixation. Moreover, osteoarthritis progression following tibial plateau fractures is common, often requiring a subsequent total knee arthroplasty (TKA). In recent years, in order to overcome the fracture healing problems and to allow immediate full weight bearing, primary TKA after tibial plateau fractures in elderly patients has gained popularity.

MATERIAL AND METHODS

from 2015 to 2019, 11 tibial plateau fractures in elderly patients with pre-existing osteoarthritis were treated with a primary TKA. Age, gender, mechanism of trauma, pre-operative autonomy level, fractures classification, degree of osteoarthritis and intraoperative data (ligamentous stability and type of implant) were collected. After a mean follow-up of 28 months, Knee Society Score (KSS), post-operative autonomy level and Forgotten Joint Score (FJS) were evaluated. The radiological assessment (signs of loosening, limb axis and patellar height indices) and complications were also recorded.

RESULTS

according to fracture type and ligamentous competence, 6 cases of posterior-stabilized (PS) design and 5 cases of semi-constrained TKA were implanted. At the final follow up, mean KSS knee score was 83±16 and mean KSS functional score was 74±15. Mean pre-operative autonomy level assessed with the Parker scale, was significantly higher than the post-operative one (7.5±1.4 vs 5.6 ± 1.3). Mean FJS was 66 ± 14. No lines of radiolucency or limb malalignment were found at the final radiological follow-up. One major complication was recorded: one acute periprosthetic infection. One patient reported a periprosthetic femoral fracture after 26 months.

CONCLUSION

Based on our and results and those reported on literature, primary TKA is a suitable option in case of tibial plateau fractures in elderly patients with pre-existing osteoarthritis and poor bone quality, in which osteosynthesis outcome may be poor. Unlike ORIF, primary TKA may allow immediate weightbearing and a faster recovery. Nevertheless, it is a demanding surgery with a significant complications rate and should be reserved for selected patients and experienced surgeons.

Histological evaluation of acetabular bone quality during revision hip arthroplasty

PURPOSE

Aim of this study was to evaluate acetabular bone vitality during revision hip arthroplasty and to compare the bone quality between revision and primary acetabular arthroplasty.

METHODS

During primary and revision total hip arthroplasty surgeries, biopsies were taken from the acetabulum after reaming. The samples (osteochondral cylinders of approximately ⩽1 cm long and 3 mm thickness), after removing the mineral component, were cut longitudinally with a thickness section of 5 µm and colored with hematoxylin-eosin dichromic dye and then evaluated histologically by optical microscopy with 40× magnification. Preoperative radiographs were evaluated.

RESULTS

According to inclusion and exclusion criteria, 14 patients formed the revision group patients (mean age: 67.9 years, average time before revision 8.8 years, SD ± 7.06) and 5 patients formed the control primary group (mean age: 61.4 years). The bone quality of the revision group was generally poorer than the primary group, while similar vitality and bone quality has been found between septic and aseptic group. Variables such as age, gender and BMI did not significantly contribute to define bone quality classes.

CONCLUSIONS

The study confirms the differences in quality and bone vitality between cases and controls and the necessity to find strategies to improve the osteointegrative processes in revision arthroplasties.

Functional results of allograft vs. autograft tendons in anterior cruciate ligament (ACL) reconstruction at 10-year follow-up

PURPOSE

The anterior cruciate ligament (ACL) tear is one of the most common sports injuries of the knee, and the arthroscopic reconstruction is the gold standard. Nevertheless, controversies about the surgical techniques and the type of graft still exist. Allografts have been considered by many surgeons as valid alternative to autografts. The aim of this study was to assess the effectiveness of allografts compared to autografts at approximately 10 years of follow-up, investigating the level of physical activity currently performed by patients of each group.

METHODS

Ninety-four patients, divided into two groups (allografts and autografts), have been retrospectively studied. The two groups did not significantly differ in preoperative sport activity level, age (mean 40.70 years for autografts and 41.23 for allografts) and characteristics. Allograft group received a fresh-frozen graft from the musculoskeletal tissues bank. Evaluations were made using the International Knee Documentation Committee (IKDC) and Lysholm score; every patient was interviewed for complications.

RESULTS

The mean follow-up time was approximately 10 years for both groups, with a minimum of 8 years. There were no statistically significant differences between the two groups. Average IKDC scores were 75.21 (SD 15.36) and 80.69 (SD 13.65) for the allograft and autograft groups, respectively. The mean Lysholm score was 87.57 (SD 9.43) for the allografts and 89.10 (SD 8.33) for the autografts. No major complications linked to the allograft tissue arose.

CONCLUSION

Both groups achieved almost the same functional outcomes at an average 10 years of follow-up, indicating fresh-frozen allografts as a reasonable alternative for ACL reconstruction.

LEVEL OF EVIDENCE

IV, Retrospective case-control study.

Third generation delta ceramic-on-ceramic bearing for total hip arthroplasty at mid-term follow-up

Purpose

to evaluate the results of Delta ceramic-on-ceramic (CoC) for total-hip-arthroplasty (THA).

Methods

261 THA using Delta-CoC, retrospectively analyzed. A 36 mm head was used in 189 cases and a 32/40 mm in the others. The series have been compared to a group of 89 THA with Forte-CoC.

Results

The Harris-Hip-Score improved from 49.1 ± 14.3 to 92.0 ± 8.9 (P < 0.001). In the Delta group there were one ceramic fracture and 2 dislocations. Two hips underwent revision. There were one revision in the Forte group for instability and one squeaking hip.

Conclusions

The new ceramic bearings provides a safe bearing for THA, with rare complications.

Bone Loss in Distal Radial Fractures Treated with A Composite Xenohybrid Bone Substitute: A Two Years Follow-Up Retrospective Study

(1) Background: Recently, surgical treatment of distal radius fractures has increased exponentially. Many locking plates' fixation systems have been developed allowing a more stable reduction and early mobilization. Sometimes, open reduction and fixation of distal radius fractures may leave a residual bone loss requiring grafting. This retrospective study reports clinical and radiologic outcomes of distal radius fractures treated with xenohybrid bone grafting in order to assess (i) the safety of the investigated bone graft; (ii) its radiological integration and biomechanical performances, and (iii) clinical outcomes of the patients; (2) Methods: We performed a retrospective study on a cohort of 19 patients. Preoperative X-ray and CT scan were performed. The mean clinical and radiographical follow-up was two years. Safety of the xenohybrid bone graft was constantly evaluated. Clinical results were assessed through the DASH score and Mayo wrist score; (3) Results: No adverse reactions, infections, and local or general complication were related to the use of xenohybrid bone graft. The radiolucency of the xenografts suggested progressive osteointegration. No evidence of bone graft resorption was detected. All the patients reached consolidation with good to excellent clinical results; and (4) Conclusions: Clinical and radiological data demonstrated that xenohybrid bone grafting promotes new bone formation and healing in osteopenic areas caused by fracture reduction.

No rest for elderly femur fracture patients: early surgery and early ambulation decrease mortality

Background

Literature has shown a significant correlation between early treatment and mortality in femur fractures, but the influence of time to ambulation on mortality has not been studied. The purpose of the present study is to evaluate whether time to ambulation is correlated to femur fracture mortality independently from time to surgery.

Patients and methods

All patients older than 65 years admitted at a level I trauma center with proximal femoral fracture during a 1-year period were included. The following data were collected: age, gender, date and time of admission to emergency department, height, weight, body mass index, type and side of fracture, ASA score, date and time of surgery, surgical time, time to ambulation, length of hospitalization, death during hospitalization, and mortality at 6 and 12 months.

Results

The study sample comprises 516 patients. The mean age was 83.6 years; ASA score was 3–5 in 53% of patients; 42.7% presented with medial fracture; mean time between admission and surgery was 48.4 h; 22.7% of patients were not able to walk during the first 10 days after fracture; mean duration of hospitalization was 13 days; and mortality was 17% at 6 months and 25% at 1 year. Early surgery and walking ability at 10 days after trauma were independently and significantly associated with mortality at 6 months (p = 0.014 and 0.002, respectively) and at 1 year (0.027 and 0.009, respectively).

Conclusions

Early surgery in femur fracture became a priority in health systems, but early postoperative physiotherapy also plays a major role in prevention of mortality: independently from surgical timing, patients who did not walk again within 10 days from surgery showed mortality rates higher than those of patients who did.

Level of evidence

IV.

Pelvic discontinuity in acetabular revisions: does CT scan overestimate it? A comparative study of diagnostic accuracy of 3D-modeling and traditional 3D CT scan

PURPOSE

3D CT scan is actually the gold standard for preoperative diagnosis of pelvic discontinuity (PD) in hip revision surgery. Aim of this study was to compare the accuracy of 3D-modeling with traditional and 3D CT scan.

MATERIALS AND METHODS

We retrospectively identified 56 patients who underwent total hip arthroplasty revisions with Paprosky Type-3 periacetabular bone defects. Preoperative X-rays, CT scans and 3D-models were blindly reviewed by two orthopedic surgeons to detect possible pelvic discontinuities. Results were compared with surgical notes. Independent sensitivities, specificities, positive predictive values and negative predictive values were calculated for X-rays, CT scan and 3D models. Analysis of interobserver reliability was performed.

RESULTS

Fifty-six patients met inclusion criteria. In nine patients, surgical notes indicated a pelvic discontinuity. On 3D CT scans, PD was identified in 25 cases for observer 1 and in 24 cases for observer 2. Analyzing 3D-models, PD was identified in eleven patients by both observers. The nine patients, with PD reported on the surgical report, were all identified with both the techniques. The specificity of standard 3D CT was 0.66 for observer 1 and 0.68 for observer 2 and increased to 0.96 for both observers with the utilization of 3D-models. The positive predictive value increased from 0.36 (observer 1) and 0.38 (observer 2) with the CT evaluation to 0.82 in the 3D-models evaluation. The analysis of 3D models was characterized by a perfect intraobserver reliability (intraobserver correlation coefficient = 1). The observers showed substantial agreement for PD classification; the kappa values were 0.96 and 0.77, respectively, for CT scan and 3D-model evaluation.

CONCLUSIONS

3D-modeling showed higher specificity than traditional and 3D CT scans in identification of PD in Paprosky Type-3 periacetabular bone defects.

Can We Predict the Progression of Vertebral Collapse in Conservative Treatment of Osteoporotic Vertebral Fractures? A 3-Year Retrospective Study of 180 Patients From the Emergency Department

BACKGROUND

Osteoporotic vertebral fractures (OVFs) have a high incidence in the elderly population and are usually treated conservatively with good outcomes. Nevertheless, failure of the conservative treatment may lead to serious complications. The aim of the study is to identify clinical, radiographic, and magnetic resonance imaging findings potentially related to the failure of the conservative treatment of OVFs.

METHODS

Data from 620 patients treated in the emergency department for vertebral fracture from 2014 to 2016 were analyzed; after patient identification and inclusion criteria, only fresh OVFs of patients older than 65 years have been included. Main outcome measurements were vertebral collapse, fracture shape types, and progression of vertebral collapse. A progression of vertebral collapse >100% was taken as an independent variable to underline the statistically significant difference among the risk factors.

RESULTS

A total of 180 patients (138 women; 42 men) and 200 OVFs were analyzed (mean age = 77 years, range = 65-94 years). Potential risks factors for the progression of vertebral collapse >100% were found when fractures occurred in the thoraco-lumbar junction. The swelling type and the bow-shaped type showed higher risk of vertebral collapse, while the concave was the most stable type of fracture with good prognosis. Traumatic fractures had lower risks of fracture progression compared to nontraumatic fractures (eg, fractures after an effort). A linear black signal pattern on short inversion time inversion recovery findings of magnetic resonance imaging corresponded to a risk of progression of the vertebral collapse.

CONCLUSIONS

Thoraco-lumbar fractures, swelling and bow-shaped fractures, and a linear black area at MR are negative prognostic factors for the failure of conservative treatment.

LEVEL OF EVIDENCE

4.

CLINICAL RELEVANCE

The identification of negative prognostic factors may lead to different strategies of treatment to prevent vertebral collapse or failure of conservative treatment.

Surgical treatment of traumatic thoracolumbar fractures: a retrospective review of 101 cases

PURPOSE

To evaluate the outcomes of vertebral stabilisation after acute traumatic thoracolumbar fractures, correlating the outcome with patient clinical data, type and location of fracture, presence of neurological damage, timing of surgical intervention and number of instrumented levels. The results have been evaluated also through the AO classification and AOSIS score.

METHODS

Retrospective analysis of 101 patients with traumatic thoracolumbar injuries from T3 to L5 operated 2011-2016 by posterior or antero-posterior fixation. The demographic data, trauma dynamics, number and type of fractures, associated lesions, timing of surgery, hospital stay, AOSIS score, RKA, SF-36 and ODI scores, pre- and post-operative neurological condition (ASIA grade), possible complications and re-interventions were evaluated for each patient.

RESULTS

Fractures mainly involved the region between T11 and L2. The probability of medullary involvement increases with the increase in severity of the main fracture type with no relation with the vertebral region. Type B and C fractures were common in the thoracic region and rare in the thoracolumbar junction. ODI and SF-36 scores were significantly better in patients with a lower AOSIS score, specifically in lesions classified as type A, amyelic and with no comorbidity. No difference was found in the clinical scores between thoracic, thoracolumbar and lumbar fractures, nor between male and female patients. None of the 10 patients with ASIA A lesion at presentation achieved any degree of recovery: 50% of them had a thoracic lesion. Re-intervention rate was 15%. Hospital stay was significantly higher in patients with type C fractures, and complication rate was on average 14% (7% in type A fractures, 16% in B and 25% in C).

CONCLUSIONS

This study confirmed the validity of the posterior approach in the surgical treatment of thoracolumbar fractures. Outcomes and complication risks are related to fracture severity. Surgical treatment can be recommended even with an AOSIS score of two or three. The combined antero-posterior approach could be useful in cases with LSC > 8, especially in the thoracolumbar region. The degree of neurological recovery depends on fracture type, location, ASIA score and presence of comorbidities. Early intervention in myelic patients allows for a better prognosis. Level of evidence III retrospective case series.

PMMA-Based Bone Cements and the Problem of Joint Arthroplasty Infections: Status and New Perspectives

Polymethyl methacrylate (PMMA)-based bone cement is a biomaterial that has been used over the last 50 years to stabilize hip and knee implants or as a bone filler. Although PMMA-based bone cement is widely used and allows a fast-primary fixation to the bone, it does not guarantee a mechanically and biologically stable interface with bone, and most of all it is prone to bacteria adhesion and infection development. In the 1970s, antibiotic-loaded bone cements were introduced to reduce the infection rate in arthroplasty; however, the efficiency of antibiotic-containing bone cement is still a debated issue. For these reasons, in recent years, the scientific community has investigated new approaches to impart antibacterial properties to PMMA bone cement. The aim of this review is to summarize the current status regarding antibiotic-loaded PMMA-based bone cements, fill the gap regarding the lack of data on antibacterial bone cement, and explore the progress of antibacterial bone cement formulations, focusing attention on the new perspectives. In particular, this review highlights the innovative study of composite bone cements containing inorganic antibacterial and bioactive phases, which are a fascinating alternative that can impart both osteointegration and antibacterial properties to PMMA-based bone cement.

How much does saving femoral head cost after acetabular fracture? Comparison between ORIF and THA

We performed a prospective study on patients with acetabular fractures treated either with internal fixation either with arthroplasty comparing clinical outcomes, quality of life, economic resources and cost efficacy in the first five years after surgery. Demographic data, diagnosis, index treatment, costs and subsequent surgeries were recorded. Patients were requested to fulfill Merle d'Aubigné and EQ-5D-5L questionnaires. Clinical differences between treatments are significant only in discharge period. Comparing respectively group with fixation and arthroplasty, cost efficacy was 5483 and 10838 euros/quality-adjusted-life years, mean global costs 23965 and 16878 € and quality of life gained in five years 2.788 and 3.175. Group of arthroplasty showed better quality of life at discharge and at one year. If choice between fixation and arthroplasty should be based only on cost-efficacy, arthroplasty should be suggested but clinical outcomes suggest to consider fixation because results at five years are not different to arthroplasty.

Bioabsorbable implants in foot trauma surgery

BACKGROUND

Resorbable osteosynthesis has been used in orthopaedic surgery for many years. However, indications for the use of these implants in the surgery of traumatic lesions of the foot have not yet been clearly defined. The aim of this study is to analyse reported experiences with the bioabsorbable devices and to suggest guidelines for their use in foot trauma surgery METHODS: We conducted a literature review to identify known indications for the use of absorbable devices in traumatic lesions of the foot. We also conducted a retrospective analysis of our registry, reviewing patients with traumatic lesions of the foot who were treated surgically with absorbable devices from November 2005 to January 2017. To this end, we analysed for each case the indication for the use of resorbable devices and the incidence of related complications.

RESULTS

Only 14 relevant studies were found. In the selected period, 76 patients were treated using bioabsorbable devices for a traumatic lesion of the foot. Nine patients were lost to follow-up or did not satisfy the inclusion criteria. Therefore, the final size of the registry was 67 patients. The average follow-up was 20.5 months (range 6-66). All the bioabsorbable devices used were screws and bars of poly-L-lactic acid (PLLA). The indications identified in the literature review and in our registry were osteosynthesis of small periarticular fragments in talus and calcaneus fractures, preliminary stabilisation of articular fragments in Sanders III calcaneal fractures and fracture-dislocations of the Lisfranc or Chopart joints. No foreign-body reactions occurred. However, in one case we registered a late mobilisation of a PLLA bar in a healed calcaneal fracture, probably as a consequence of surgical malpositioning of the device. All the operated lesions demonstrated a normal healing time, and the complication rate was comparable with those of other types of osteosynthesis.

CONCLUSION

In foot trauma surgery the use of absorbable devices can give advantages. The most clearly defined indications are osteosynthesis of peri-articular or articular fragments in talus and calcaneus fractures, Sanders III calcaneal fractures and fracture-dislocations of Lisfranc's or Chopart's joints. Foreign-body reactions are rare and seem not to present a problem.

Free composite groin flap to solve a complex loss of tissue in a traumatic injury of the foot: A case report

Severe traumatic losses of soft tissues and bone at foot and ankle level are often treated by means of amputation, but this may involve important psychological and anatomic consequences for the patient. If there are good vascular conditions, reconstruction by means of composite free flaps is often the only alternative to this demolitive treatment. The transfer of composite free flaps that include vascularized bone from various donor sites may provide anatomical reconstruction and recovery of function of the foot and ankle. If plantar skin and its sensation are present, these techniques may represent a good choice in the treatment of complex injuries of the foot, and by means of skeletal morphological reconstruction, they may give good functional results. With these premises, we report a case in which was used a groin flap to fill and solve a complex defect of bone and soft tissues of midfoot in a gunshot injury.

Concentrated adipose tissue infusion for the treatment of knee osteoarthritis: clinical and histological observations

PURPOSE

Osteoarthritis (OA) is characterized by articular cartilage degeneration and subchondral bone sclerosis. OA can benefit of non-surgical treatments with collagenase-isolated stromal vascular fraction (SVF) or cultured-expanded mesenchymal stem cells (ASCs). To avoid high manipulation of the lipoaspirate needed to obtain ASCs and SVF, we investigated whether articular infusions of autologous concentrated adipose tissue are an effective treatment for knee OA patients.

METHODS

The knee of 20 OA patients was intra-articularly injected with autologous concentrated adipose tissue, obtained after centrifugation of lipoaspirate. Patients' articular functionality and pain were evaluated by VAS and WOMAC scores at three, six and 18 months from infusion. The osteogenic and chondrogenic ability of ASCs contained in the injected adipose tissue was studied in in vitro primary osteoblast and chondrocyte cell cultures, also plated on 3D-bone scaffold. Knee articular biopsies of patients previously treated with adipose tissue were analyzed. Immunohistochemistry (IHC) and scanning electron microscopy (SEM) were performed to detect cell differentiation and tissue regeneration.

RESULTS

The treatment resulted safe, and all patients reported an improvement in terms of pain reduction and increase of function. According to the osteogenic or chondrogenic stimulation, ASCs expressed alkaline phosphatase or aggrecan, respectively. The presence of a layer of newly formed tissue was visualized by IHC staining and SEM. The biopsy of previously treated knee joints showed new tissue formation, starting from the bone side of the osteochondral lesion.

CONCLUSIONS

Overall our data indicate that adipose tissue infusion stimulates tissue regeneration and might be considered a safe treatment for knee OA.

Does metal porosity affect metal ion release in blood and urine following total hip arthroplasty? A short term study

INTRODUCTION

The surface area of exposed metal in a trabecular-titanium acetabular component is wider compared to traditional-titanium implants. The purpose of this study is to establish if this increase in surface area can lead to a significant increase in systemic metal levels.

METHODS

19 patients with conventional acetabular component and 19 with trabecular-titanium cup were compared. Aluminum, Vanadium and Titanium in blood and urine were assessed before surgery and at intervals for 2 years. The samples were analysed using an inductively coupled plasma mass spectrometry.

RESULTS

Patients with trabecular-titanium did not have significantly higher metal ion levels compared to patients with conventional cups up to 2 years. A trend over time was statistically significant in both blood and urine for aluminum and titanium concentrations.

CONCLUSIONS

The three-dimensionality and the wide surface of the trabecular-titanium acetabular component did not affect metal ion release compared to traditional implants after 2 years.

Unexpected Listeria monocytogenes detection with a dithiothreitol-based device during an aseptic hip revision

Prosthetic joint infection diagnosis is often difficult since biofilm-embedded microorganisms attach well to the prosthetic surfaces and resist their detection by conventional methods. DL-dithiothreitol has been described as a valid method for biofilm detachment on orthopedic devices. We report the case of an occasional detection of Listeria monocytogenes in a non immuno-compromised patient with a preoperative diagnosis of aseptic loosening. The infection diagnosis due to such rare bacteria was made postoperatively, thanks to a DL-dithiothreitol-based device. This may be considered a feasible approach for the microbiological analysis of prosthetic joint infection, considering that a prompt diagnosis of such biofilm-associated infections could bring some advantages, such as an early and appropriate antibiotic therapy administration and a reduction of undiagnosed infections.

Tripled semitendinosus with single harvesting is as effective but less invasive compared to standard gracilis-semitendinosus harvesting

Introduction

The anterior cruciate ligament (ACL) reconstruction with pes anserinus tendons has been increasingly used throughout the last years. Although less invasive compared to other autologous grafts, a reduction of internal rotation and flexion strength after gracilis and semitendinosus harvesting has been reported. Harvesting one tendon instead of two from the pes anserinus can reduce the deficit of the knee flexor strength and improve the functional recover without weakening the reconstructed ligament.

Methods

Forty-five (45) patients who had ACL reconstruction with triple semitendinosus graft (ST3) have been compared with other 45 similar patients who had ACL reconstruction with double gracilis-semitendinosus tendons (GST). Patients have been evaluated at a minimum of 12 months after surgery: IKDC scale, KT-1000, One Leg Hop Test for the objective stability; Isokinetic test for the strength; Tegner scale, Lysholm and IKDC subjective evaluation form for the function.

Results

No differences have been detected between the groups for the objective item assessed. Male patients' subjective IKDC score was statistically better for the ST3 group. Recreational soccer players showed a higher Lysholm and subjective IKDC score in ST3 group compared to GST group. There was no difference regarding the return to sport.

Conclusion

ST3 guarantees the same objective knee stability compared to a GST. It is a viable option for ACL reconstruction that allows a better preservation of patient's anatomy and a less invasive harvesting surgery.

Level of evidence

III b, case control study.

Combined Intra- and Extra-Articular Technique in Revision Anterior Cruciate Ligament Reconstruction

Purpose  The aim of the study was to evaluate the “over the top” (OTT) nonanatomical technique for revision of anterior cruciate ligament (ACL) reconstruction.

Methods  Twenty-four patients with a mean age of 31.9 ± 11.2 years underwent revision of ACL reconstruction using OTT technique. International Knee Documentation Committee (IKDC) score, Knee Injury and Osteoarthritis Outcome Score (KOOS), Lysholm score, Tegner score, Subjective Patient Outcome for Return to Sport (SPORTS) score, Anterior Cruciate Ligament-Return to Sport After Injury (ACL-RSI) scale, and KT-1000 evaluation were recorded at a mean follow-up of 30.7 ± 18.9 months.

Results  Postoperatively, the IKDC objective total score significantly improved ( p  = 0.0046). The KOOS, Lysholm, and Tegner scores also improved, but the results were not statistically significant (62.4 vs. 72.6, 6.5 vs. 75.8, and 4.1 vs. 6.0, respectively). The subjective IKDC evaluation score improved from an average of 51.1 points to 63.7 points at the last follow-up ( p  = 0.0027). The RTP prevalence was 81.8%, with 44.4% of the patients returning to the same preinjury level. According to the SPORTS score, 16.6% of patients played sport without limitations in activity and performance. The average ACL-RSI score was 52.1 ± 27.0. No major complications were reported. A total of 21.5% of patients underwent surgical removal of staples. The failure prevalence was 14.3% and the cumulative survivorship, calculated using the Kaplan–Meier method, was equal to 70% at 60 months of follow-up.

Conclusion  The OTT technique in the revision ACL reconstruction provided improvement in objective and subjective scores, good RTP prevalence, and acceptable rate of complication and failure. One of the advantages was the possibility to avoid the femoral tunnel.

Level of Evidence  Level IV, therapeutic case series.

Ultra-High Molecular Weight Polyethylene: Influence of the Chemical, Physical and Mechanical Properties on the Wear Behavior. A Review

Ultra-high molecular weight polyethylene (UHMWPE) is the most common bearing material in total joint arthroplasty due to its unique combination of superior mechanical properties and wear resistance over other polymers. A great deal of research in recent decades has focused on further improving its performances, in order to provide durable implants in young and active patients. From "historical", gamma-air sterilized polyethylenes, to the so-called first and second generation of highly crosslinked materials, a variety of different formulations have progressively appeared in the market. This paper reviews the structure-properties relationship of these materials, with a particular emphasis on the in vitro and in vivo wear performances, through an analysis of the existing literature.

Patient specific instrumentation in total knee arthroplasty: a state of the art

Patient specific instrumentation (PSI) is a modern technique in total knee arthroplasty (TKA) aiming to facilitate the implant of the prosthesis. The customized cutting blocks of the PSI are generated from pre-operative three-dimensional model, using computed tomography (CT) or magnetic resonance imaging (MRI). A correct surgical plan is mandatory for a good surgical implant. The PSI guide takes into account any slight deformities or osteophytes and applies preoperative planning for bone resection, using the pre-determined implant size, position, and rotation. The apparent benefits of this technology are that neutral postoperative alignment is more reproducible, surgical time is decreased, and the entire procedure results more efficient and cost-effective. The use of PSI is indicated when advanced osteoarthritis, severe pain, and limited function/walking ability are present, such as in a standard instrumentation TKA. In addition to that, PSI finds its indication when intra-medullary guides cannot be used. For example, when there is a post-traumatic femoral deformity. Large debates have taken place about this topic during the last years and, at the moment, there is no consensus in literature regarding the accuracy and reliability of PSI as many studies have shown controversial and inconsistent results. Literature does not suggest PSI techniques as a gold standard in TKA, and therefore it cannot be recommended as a standard technique in standard, not complicated primary TKA. Moreover, literature does not underline any improvement in components alignment, surgical time, blood loss or functional outcomes. Nevertheless, many patients who underwent TKA suffered a previous trauma. In case of deformities, like femoral or tibial fractures healed with a malalignment, preoperative planning may result difficult, and some intra-operative technical difficulties can occur, such as the use of intra-medullar rod. In these selected cases, PSIs may be very useful to avoid errors in alignment and planning.

Do crosslinking and vitamin E stabilization influence microbial adhesions on UHMWPE-based biomaterials?

BACKGROUND

Microorganism adhesion on polyethylene for total joint arthroplasty is a concern. Many studies have focused on vitamin E-stabilized ultrahigh-molecular-weight polyethylene (UHMWPE), whereas first-generation, highly crosslinked UHMWPE, which is the most commonly used in clinical practice, has been scarcely evaluated.

QUESTIONS/PURPOSES

We aimed (1) to compare the adherence of Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, and Candida albicans with virgin (untreated) UHMWPE (PE) and crosslinked UHMWPE (XLPE); (2) to correlate the results with the biomaterial surface properties; and (3) to determine whether the decreased adhesion on vitamin E-stabilized UHMWPE (VE-PE) previously recorded for bacteria can also be confirmed for C albicans.

METHODS

Microbial adhesion of biofilm-producing American Type Culture Collection (ATCC) and clinical strains on XLPE and VE-PE were compared with PE at 3, 7, 24, and 48 hours of incubation and quantified, as colony forming units (CFU)/mL, using a sonication protocol. Sample surfaces were characterized by scanning electron microscopy, roughness and contact angle measurements, attenuated total reflection-Fourier transform infrared spectroscopy, and x-ray photoelectron spectroscopy (XPS) to reveal qualitative differences in surface composition and topography that could influence the microbial adhesion. The results were analyzed by descriptive statistics and tested by unpaired t-tests.

RESULTS

All microorganisms, both ATCC and clinical strains, showed lower adhesion (p < 0.05) on XLPE with adhesion percentages ranging from 18% to 25%, compared with PE with adhesion percentages ranging from 51% to 55%, after 48 hours. Only the ATCC S epidermidis showed a reduced adhesion profile even at 3 hours (adhesion ratio of 14% on XLPE versus 50% on PE) and 24 hours (19% on XLPE versus 55% on PE) of incubation. ATCC and clinical C albicans were less adherent to XLPE than to PE (p < 0.05) showing even at the earlier incubation time points adhesion values always of 10(3) CFU/mL and 10(4) CFU/mL, respectively. Roughness and contact angle were 0.8 ± 0.2 μm and 92° ± 3°, respectively, with no differences among samples. Qualitative differences in the surface chemical composition were revealed by XPS only. A confirmation of the decreased adhesion on VE-PE respect to PE was also registered here for C albicans strains (p < 0.05).

CONCLUSIONS

Vitamin E stabilization and crosslinking of UHMWPE are capable of reducing microbial adhesion. Further studies are needed to fully elucidate the mechanisms of modulation of microbial adhesion to medical-grade UHMWPE.

CLINICAL RELEVANCE

Our results suggest that VE-PE and XLPE may have an added benefit of being more resistant to bacterial adhesion, even fungal strains.

Therapeutic ultrasound in physical medicine and rehabilitation: characterization and assessment of its physical effects on joint-mimicking phantoms

The aim of the study described here was to quantitatively assess thermal and mechanical effects of therapeutic ultrasound (US) by sonicating a joint-mimicking phantom, made of muscle-equivalent material, using clinical US equipment. The phantom contains two bone disks simulating a deep joint (treated at 1 MHz) and a superficial joint (3 MHz). Thermal probes were inserted in fixed positions. To test the mechanical (cavitational) effects, we used a latex balloon filled with oxygen-loaded nanobubbles; the dimensions of the oxygen-loaded nanobubbles were determined before and after sonication. Significant increases in temperature (up to 17°C) with fixed field using continuous waves were detected both in front of and behind the bones, depending on the US mode (continuous wave vs. pulsed wave) and on the treatment modality (fixed vs. massage). We found no significant differences in mechanical effects. Although limited by the in vitro design (no blood perfusion, no metabolic compensation), the results can be used to guide operators in their choice of the best US treatment modality for a specific joint.

Interplay between surface properties of standard, vitamin E blended and oxidised ultra high molecular weight polyethylene used in total joint replacement and adhesion of Staphylococcus aureus and Escherichia coli

We have assessed the different adhesive properties of some of the most common bacteria associated with periprosthetic joint infection on various types of ultra high molecular Weight Polyethylene (UHMWPE). Quantitative in vitro analysis of the adhesion of biofilm producing strains of Staphylococcus aureus and Escherichia coli to physically and chemically characterised standard UHMWPE (PE), vitamin E blended UHMWPE (VE-PE) and oxidised UHMWPE (OX-PE) was performed using a sonication protocol. A significant decreased bacterial adhesion was registered for both strains on VE-PE, in comparison with that observed on PE, within 48 hours of observation (S. aureus p = 0.024 and E. coli p = 0.008). Since Vitamin E reduces bacterial adhesive ability, VE-stabilised UHMWPE could be valuable in joint replacement by presenting excellent mechanical properties, while reducing bacterial adhesiveness.

Incontinentia pigmenti: a rare pathology with complex rehabilitative aspects

PURPOSE

Incontinentia pigmenti (IP), or Bloch-Sulzberger syndrome, is a rare X-linked dominant genetic disorder with multisystem involvement. To our knowledge, there are no previous reports about rehabilitation in IP adult with intact cognitive development. We report a 20-year-old lady with IP managed and followed into adulthood.

METHOD

Patient management and rehabilitation programs from birth to the last follow-up.

RESULTS

There was normal cognitive development despite magnetic resonance imaging (MRI) evidence of white matter, corpus callosum and brainstem hypoplasia. Extensor spasticity was present on both lower limbs for which she underwent rehabilitation from the age of one. Botulinum toxin injections were performed and when she was 15 years old she underwent functional surgery.

CONCLUSION

The absence of mental retardation in our patient enabled us to carry out an active rehabilitation program and provide her with maximum independence in locomotion and in activities of daily living. IMPLICATIONS FOR REHABILIATION: Incontinentia pigmenti (Bloch-Sulzberger syndrome). Incontinentia pigmenti is a rare X-linked dominant genetic disorder with multisystemic involvement. Skin lesions, neurological impairments, motormental retardation, skeletal congenital defects and ophthalmologic involvement are IP most frequent manifestations. Due to the complex multisystem involvement resulting in severe long-term disability, patients with IP require a multidisciplinary team approach for rehabilitation. In IP patients, rehabilitation interventions should always take into consideration the individual phenotype expression, child's physical development and personal needs.

Endo-Modell rotating-hinge total knee for revision total knee arthroplasty

The goal of this study was to analyze the clinical and radiographic results and the survival rate of a series of rotating-hinge implants used for revision total knee arthroplasties in mild and severe instability. Between December 1991 and June 2004, fifty-three revision total knee arthroplasties were performed using the Endo-Modell (Waldemar LINK GmbH and Co, Hamburg, Germany) rotating-hinge prosthesis; 7 (13.2%) patients underwent partial revision of a previous Endo-Modell. All patients were evaluated preoperatively, 3 and 6 months postoperatively, and annually thereafter using the Hospital for Special Surgery (HSS) knee score and the Knee Society Roentgenographic Evaluation System (KS-RES). Mean follow-up was 155.2±40.1 months (range, 78-240 months), with 32 patients examined at the final follow-up. All HSS knee scores increased from preoperatively to last follow-up. No statistically significance differences were found in the HSS knee scores between septic and aseptic revisions and between total or partial revisions. Progressive radiolucent lines were detected in 8 (25%) patients. Implant failure occurred in 11 (20.7%) patients; the cumulative survival of the implants was 80.4% at 150 months for the final 32 patients. The authors recommend use of this implant for revision total knee arthroplasty, especially in patients with severe instability and bone loss.

Comparison of fixed and mobile-bearing total knee arthroplasty at a mean follow-up of 116 months

BACKGROUND

The superiority of mobile-bearing total knee arthroplasty implants over fixed-bearing implants, or vice versa, is still debated.

METHODS

A series of patients with similar clinical and radiographic characteristics were treated consecutively with 100 fixed-bearing followed by 100 rotating-platform implants. Patients underwent prospective clinical and radiographic evaluation.

RESULTS

The mean duration of follow-up was 116 months (range, sixty-one to 144 months). Clinical, radiographic, and implant survival outcomes were compared. No significant differences between the mobile-bearing and fixed-bearing groups were found with respect to the clinical outcome or cumulative implant survival at the time of the latest follow-up. Three of the fixed-bearing implants and one of the rotating-platform implants had required revision surgery.

CONCLUSIONS

No differences between mobile-bearing and fixed-bearing designs were demonstrated at a mean of 116 months of follow-up.

Results with 98 Endo-Modell rotating hinge prostheses for primary knee arthroplasty

Rotating hinge knee prostheses have been developed as an advancement of the fixed hinge models. Some authors suggest that this type of prosthesis is associated with a greater risk of aseptic loosening because of the increased stresses to the bone-prosthesis interface; therefore, they are scarcely used as primary implants. The current authors evaluated of a series of 98 rotating hinge knee arthroplasties Endo-Modell (Waldemar LINK GmbH and Co, Hamburg, Germany) implanted for knee osteoarthritis. The Hospital for Special Surgery Knee Score and the Knee Society Score were used for the clinical and radiographic evaluation. Log-rank or Wilcoxon tests were used to test the statistical significances, and the Kaplan-Maier method was used to calculate the implant survival probability. After a medium follow-up of approximately 174 months, the clinical scores showed a statistically significant improvement from the pre- to postoperative period. The complication rate was high, and the cumulative implants survival rate was 88.7% at 1 year, 85.9% at 5 years, 79.8% at 10 years, and 75.8% at 15 years. The Endo-Modell rotating hinge implants demonstrated no significant risk of aseptic loosening, and the hinge was not a primary cause of failure. However, the overall failure rate was higher than that of unhinged implants; therefore, this prosthesis is recommended for cases of instability and revision rather than primary knee arthroplasty.

Rotating-hinge total knee for revision total knee arthroplasty

Rotating-hinge knee implants are used for revision total knee arthroplasty in patients with severe ligament instability and bone loss. This study evaluated the outcomes of a series of rotating-hinge knees. Thirty-one NexGen Rotating Hinge Knees (Zimmer, Warsaw, Indiana) were implanted in 29 patients (2 bilateral), with an average age of 72.8 years. Indications for surgery were aseptic loosening (n=23), septic loosenings (n=4), tibiofemoral instability (n=3), and wear (n=1). The Hospital for Special Surgery Knee Score and the Knee Society Roentgenographic Evaluation System were used. Statistical and cumulative survival rate analyses were performed. Average follow-up was 60.3 months (range, 32-100 months). The Hospital for Special Surgery Knee Score results indicated statistically significant improvement; the total score increased from 65.5 preoperatively to 88.4 postoperatively. Average range of motion increased from 90.9° preoperatively to 114.4° postoperatively. Radiographs showed no periprosthetic bone fractures or implant ruptures. Radiolucent lines were found in 20 of 26 patients and were progressive in 2 (both revised). Complications occurred in 10 patients. The rigidity of the hinge may be associated with a risk of aseptic loosening due to the increased stress transfer to the bone from the prosthesis through the locked hinge. Rotating-hinge knee implants provided acceptable mid-term outcomes for revision knee surgery with ligamentous instability. They are not at higher risk for early loosening unless short tibial stems are used. The high percentage of failures is more related to the complex surgery and to the status of the patients than to the hinged mechanism.

Arthroscopic treatment of hip chondral defects: autologous chondrocyte transplantation versus simple debridement--a pilot study

PURPOSE

To compare the effectiveness of simple arthroscopic debridement versus arthroscopic autologous chondrocyte transplantation (ACT) for the treatment of hip chondral lesions.

METHODS

We carried out a controlled retrospective study of 30 patients affected by a post-traumatic hip chondropathy of the third or fourth degree, according to the Outerbridge classification, measuring 2 cm² in area or more. Of these patients, 15 underwent arthroscopic ACT, whereas the other 15 underwent arthroscopic debridement. The 2 groups were similar in age, sex, degree, and location of the pathology. All the patients were assessed before and after the procedure with the Harris Hip Score (HHS).

RESULTS

In both groups the mean follow-up was approximately 74 months (range, 72 to 76 months). The mean size of the defect was 2.6 cm². The patients who underwent ACT (group A) improved after the procedure compared with the group that underwent debridement alone (group B). The mean HHS preoperatively was 48.3 (95% confidence interval [CI], 45.4 to 51.2) in group A and 46 (95% CI, 42.7 to 49.3) in group B (P = .428 [no significant difference]). The final HHS was 87.4 (95% CI, 84.3 to 90.5) in group A and 56.3 (95% CI, 54.4 to 58.7) in group B (P < .001 [significant difference]).

CONCLUSIONS

This study indicates that an ACT procedure can be used in the hip for acetabular chondral defects.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Vitamin E blended UHMWPE may have the potential to reduce bacterial adhesive ability

Biomaterial-associated infection (BAI), a clinical problem resulting in septic failure of joint replacement implants, is initiated by bacterial adhesion, often by Staphylococcus epidermidis. Ultra high molecular weight polyethylene (UHMWPE) is a material of choice for joint replacement; reducing the adhesion of S. epidermidis to the polymer could be a means to decrease infection. We examined the adhesion of two ATCC and one clinical strain of S. epidermidis to standard polyethylene (PE), vitamin E blended UHMWPE (VE-PE), and oxidized UHMWPE (OX-PE) after different incubation times: a significant (p < 0.01) decrease in the adhered staphylococci on VE-PE and a significantly higher incidence of the dislodged biofilm bacteria on OX-PE was observed compared with that registered on PE. With attenuated total reflectance (ATR)-FTIR spectroscopy before and after suspension in bacterial medium for 48 h, new absorptions were observed mainly in OX-PE, indicating adsorption of protein-like substances on the polymer surface. We hypothesized that the different hydrophilicity of the surfaces with different chemical characteristics influenced protein adsorption and bacterial adhesion. These results may have clinical implications concerning the prevention of septic loosening: the VE-PE could have the potential to reduce S. epidermidis adhesive ability if the preliminary data observed in these selected strains is further confirmed, as diversity among clinical strains is well known. 

The relative effects of radiation crosslinking and type of counterface on the wear resistance of ultrahigh-molecular-weight polyethylene

The lifetime of total joint replacement prostheses utilizing ultrahigh-molecular-weight polyethylene (UHMWPE) components has historically been determined by their wear resistance. It has been discovered that radiation crosslinking of UHMWPE can substantially increase its wear resistance. However, it is also well recognized that there is a radiation-dose-dependent decrease in several important mechanical properties of UHMWPE, such as fracture toughness and resistance to fatigue crack propagation. In this study, the effect of radiation crosslinking (followed by remelting) on the morphology, tensile properties and wear resistance of UHMWPE was investigated. Wear tests were conducted against both the commonly used cobalt-chromium counterface polished to implant grade smoothness as well as a smoother ceramic (alumina) counterface. The results showed that 50kGy dose radiation crosslinking increased the wear resistance of UHMWPE against the cobalt-chromium counterface 7-fold, but the coupling of remelted, crosslinked UHMWPE against the smoother alumina counterface led to a 20-fold increase in wear resistance. This study shows that the use of an alumina counterface would circumvent the need to use a high radiation dose in crosslinking UHMWPE, associated with poor mechanical properties, without compromising wear resistance.

Antibiotic-loaded cement in orthopedic surgery: a review

Infections in orthopaedic surgery are a serious issue. Antibiotic-loaded bone cement was developed for the treatment of infected joint arthroplasties and for prophylaxes in total joint replacement in selected cases. Despite the widespread use of the antibiotic-loaded bone cement in orthopedics, many issues are still unclear or controversial: bacterial adhesion and antibiotic resistance, modification of mechanical properties which follows the addition of the antibiotic, factors influencing the release of the antibiotic from the cement and the role of the surface, the method for mixing the cement and the antibiotic, the choice and the effectiveness of the antibiotic, the combination of two or more antibiotics, and the toxicity. This review discusses all these topics, focusing on properties, merits, and defects of the antibiotic loaded cement. The final objective is to provide the orthopaedic surgeons clear and concise information for the correct choice of cement in their clinical practice.

Cemented fixed-bearing PFC total knee arthroplasty: survival and failure analysis at 12-17 years

BACKGROUND

Total knee arthroplasty (TKA) is the appropriate treatment for degenerative pathology of the knee. Implant surveillance is mandatory to improve clinical results. We present the long-term results of a series of consecutive TKA Press Fit Condylar (J&J), cemented fixed bearing with selective patellar resurfacing in nonselected patients.

MATERIALS AND METHODS

In this prospective case series, 223 TKA were clinically and radiographically evaluated using the Hospital for Special Surgery (HSS) knee score and the Knee Society Roentgenographic Evaluation and Scoring System.

RESULTS

There were 197 patients, with an average age of 68.4 years [95% confidence interval (CI) 52.7-84.1 years]; 49 arthroplasties were implanted in men (21.1%) and 184 (78.9%) in women. The average follow-up was approximately 13.5 years (162.1 months; 95% CI 132.3-191.9), and it was possible to evaluate 179 implants (76.8% of the implanted prosthesis) in 176 patients. The average HSS score increased from 61.5 (95% CI 60.4-62.7) to 89.4 (95% CI 87.7-.93.5) points. The cumulative average survival rate at 15 years (the endpoint being failure with revision) was 90.6%  ± 2% standard deviation. Resurfacing the patella did not make a difference in terms of implant survival. Progressive radiolucent lines were observed around 20 implants (14.3%); all were revised.

CONCLUSIONS

The PFC system is an excellent prosthetic solution. Early clinical complications, mechanical axis and patellar resurfacing do not correlate with implant failure, whereas progressive radiolucent lines do.

In vitro comparison between commercially and manually mixed antibiotic-loaded bone cements

PURPOSE

The purpose of this study is the evaluation of the differences and, eventually, of the advantages or disadvantages of manual formulations with respect to industrial ones.

METHODS

Medical-grade bone cements (Palacos R® and Palacos LV®), based on poly-methyl methacrylate (PMMA) and used clinically in several cemented prosthetic devices were manually enriched with gentamicin sulphate during preparation and then compared with a commercially-available, antibiotic-loaded cement (Palacos R+G®) by means of an in vitro antibacterial test (inhibition zone evaluation). The purpose of this study was to evaluate the differences and advantages or disadvantages, if any, of manual formulations compared to commercial ones. The use of a different antibiotic (vancomycin) alone or in addition to gentamicin-containing bone cements was also considered.

RESULTS AND CONCLUSION

The commercial formulation produces an inhibition zone that is a bit larger and more regular than the manually mixed preparation. The vancomycin halo is smaller but clearer than the gentamicin halo. The addition of vancomycin to gentamicin-containing bone cements does not significantly increase the halo dimensions but could be an interesting strategy in the prevention of multiple and resistant infections.