Treatment of Large Cartilage Defects in the Knee by Hydrogel-Based Autologous Chondrocyte Implantation: Two-Year Results of a Prospective, Multicenter, Single-Arm Phase III Trial.

OBJECTIVE: To evaluate the clinical outcome of a hydrogel-based autologous chondrocyte implantation (ACI) for large articular cartilage defects in the knee joint. DESIGN: Prospective, multicenter, single-arm, phase III clinical trial. ACI was performed in 100 patients with focal full-thickness cartilage defects ranging from 4 to 12 cm2 in size. The primary outcome measure was the responder rate at 2 years using the Knee Injury and Osteoarthritis Outcome Score (KOOS). RESULTS: Two years after ACI treatment, 93% of patients were KOOS responders having improved by ≥10 points compared with their pre-operative level. The primary endpoint of the study was met and demonstrated that the KOOS response rate is markedly greater than 40% with a lower 95% CI (confidence interval) of 86.1, more than twice the pre-specified no-effect level. KOOS improvement (least squares mean) was 42.0 ± 1.8 points (95% CI between 38.4 and 45.7). Mean changes from baseline were significant in the overall KOOS and in all 5 KOOS subscores from Month 3 (first measurement) to Month 24 (inclusive) (P < 0.0001). The mean MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score after 24 months reached 80.0 points (95% CI: 70.0-90.0 points) and 92.1 points in lesions ≤ 5 cm2. CONCLUSIONS: Overall, hydrogel-based ACI proved to be a valuable treatment option for patients with large cartilage defects in the knee as demonstrated by early, statistically significant, and clinically meaningful improvement up to 2 years follow-up. Parallel to the clinical improvements, MRI analyses suggested increasing maturation, re-organization, and integration of the repair tissue. TRIAL REGISTRATION: NCT03319797; EudraCT No.: 2016-002817-22.

Investigation of Mechanical Properties of Twin Wire Arc Repair of Cast Iron Components.

Twin wire arc is a commonly used thermal spray technology for application of steel coatings to cast iron components. Hardness and adhesion strength are critical properties of such coatings, and significant research is available reporting these properties. However, the lamellar structure of the coatings and residual stresses induced during the coating process leads to significantly different behavior in bending applications than in purely tensile applications which are evaluated by the standard adhesion test. In addition, microstructural features that are controlled by certain process parameters during deposition of the coating can have a significant effect on these properties. This work relates the hardness, adhesion strength, and wear resistance to the coating microstructure and assesses the related bending strength and failure mode. Comparisons between bend tests and pull-off adhesion tests show significant differences to consider when designing a twin wire arc coating.

Modern Treatment of Recurrent Patellofemoral Instability - Combined Medial Patellofemoral Ligament Reconstruction and Tibial Tubercle Transfer.

PURPOSE OF THE STUDY The treatment of recurrent patellofemoral instability has undergone a paradigm change during the last 15 years. Instead of non-anatomical operations, the current concept favors the reconstruction of injured structures and the normalization of the biomechanical environment. Our aim was to briefly summarize the etiology, diagnostic regimen, and therapeutic decision making of this varied patient group and to review our own patients who underwent combined medial patellofemoral ligament reconstrucion and tibial tubercle transfer. MATERIAL AND METHODS Between 2015-2017 we performed combined ligament reconstruction and tubercle transfer for recurrent patellofemoral instability on 10 patients. The patients were examined for the degree of trochlea dysplasia, height of the patella, tibial tubercle trochlear groove distance. Additional intraarticular abnormalities were noted. The patients were assessed preoperatively and at follow-up using the Tegner Activity Scale and the Kujala score. Return to sports was also examined. RESULTS The average age of our patients was 22 years (15-40). We had 6 female patients and 4 male patient. The average followup time was 29 months (12-44). 9 patients had a medializing of the tibial tubercle, whilst one patient had a pure distalization to go along with the medial patellofemoral ligament reconstruction using PEEK tenodesis screws. We had no redislocations up to the last follow-up and patients were able to return to their previous activity level and/or sporting activity. The Kujala score improved from an average preoperative value of 48.9 (32-58) to an average follow-up value of 88.6 (70-97). DISCUSSION The essential steps in the treatment of recurrent patellofemoral instability are a thorough physical examination, appropriate imaging and the individual correction of the uncovered anatomical abnormalities. Neither isolated lateral retinacular release, nor medial capsular reefing can preictably produce satisfactory results. CONCLUSIONS Medial patellofemoral ligament reconstruction with tibial tubercle transfer (medializing and/or distalization) is a reliable surgical technique, that provides long term patellar stabilty in this selected group of young patients. Key words: patellar dislocation, joint instability, ligaments, tendon transfer.

An interobserver reliability comparison between the Orthopaedic Trauma Association's open fracture classification and the Gustilo and Anderson classification.

AIMS: To evaluate interobserver reliability of the Orthopaedic Trauma Association's open fracture classification system (OTA-OFC). PATIENTS AND METHODS: Patients of any age with a first presentation of an open long bone fracture were included. Standard radiographs, wound photographs, and a short clinical description were given to eight orthopaedic surgeons, who independently evaluated the injury using both the Gustilo and Anderson (GA) and OTA-OFC classifications. The responses were compared for variability using Cohen's kappa. RESULTS: The overall interobserver agreement was ĸ = 0.44 for the GA classification and ĸ = 0.49 for OTA-OFC, which reflects moderate agreement (0.41 to 0.60) for both classifications. The agreement in the five categories of OTA-OFC was: for skin, ĸ = 0.55 (moderate); for muscle, ĸ = 0.44 (moderate); for arterial injury, ĸ = 0.74 (substantial); for contamination, ĸ = 0.35 (fair); and for bone loss, ĸ = 0.41 (moderate). CONCLUSION: Although the OTA-OFC, with similar interobserver agreement to GA, offers a more detailed description of open fractures, further development may be needed to make it a reliable and robust tool. Cite this article: Bone Joint J 2018;100-B:242-6.

Conservative treatment of periprosthetic femur fractures around metaphyseal short stems - A feasible option?

Periprosthetic femoral fractures are rare but significant events following total hip replacement. Metaphyseal short stems have recently been popularized as a bone preserving alternative to conventional uncemented total hip replacement. We present two periprosthetic femur fractures which occurred around two different metaphyseal uncemented stem designs. Successful conservative treatment was possible in both cases achieving bony union and excellent clinical results.

Impact of change of knee prosthesis on early clinical outcomes in a large volume arthroplasty centre.

INTRODUCTION: The aim of our study was to investigate the effect of changing the default knee prosthesis in a high volume dedicated arthroplasty unit from DePuy's PFC(®) Sigma(®) to Smith & Nephew's Genesis™ II. METHODS: A retrospective analysis was performed of prospective data on primary total knee replacements (TKRs) from January 2009 until December 2011. This provided information on the operative time, length of stay, pain at mobilisation, radiography analysis, any complications, and readmission at 30 and 60 days. RESULTS: The total numbers of primary TKRs using the PFC(®) and Genesis™ II prostheses were 1,061 and 1,268 respectively. The results showed a slight increase (maximum of five minutes) in the operative time for all the surgeons except one surgeon, whose operative time reduced by an average of seven minutes. There was no significant adverse outcome after the change in the knee implant. There was no clinically significant increase in the length of stay, pain at mobilisation or complication rates. There was a twofold increase in the wastage of the implant in the Genesis™ II group in the initial learning period. CONCLUSIONS: Through a competitive process of implant tendering, we have successfully introduced a new implant into a large elective orthopaedic unit. This has resulted in significant financial savings without adversely affecting our clinical practice or patient outcome.

The treatment of traumatic shock: recent advances and unresolved questions.

Uncontrolled bleeding remains a leading cause of potentially preventable death after trauma. Timely, adequate resuscitation in traumatic shock is an essential, lifesaving aspect of polytrauma care. Whilst basic principles in the treatment of traumatic shock remain the same-achieving hemorrhage control and replacing lost volume, the way this is achieved has changed significantly in the last five years. The abandonment of blood pressure driven uncontrolled fluid resuscitation, the introduction of the concept of hemostatic resuscitation, and the increasing use of massive transfusion protocols have all contributed to an improvement in timely access to various blood products. The increase in knowledge regarding the pathophysiology of trauma, the availability of adjuncts, and the array of resuscitation monitoring options available have all contributed to a potentially improved approach to resuscitation. The purpose of this report is to review the most important advances in traumatic shock therapy in the last five years.

Percutaneous decompression for the treatment of Mueller-Weiss syndrome.

This report describes the case of a young athlete, who presented with a painful foot and was eventually diagnosed with early-stage Mueller-Weiss syndrome (spontaneous osteonecrosis of the navicular) by MRI. As non-operative management was unsuccessful, a percutaneous decompression of the navicular was performed. The patient made a full recovery and was able to return to her previous level of sporting activity. Subsequent imaging showed complete remodelling of the bony architecture of the affected navicular.

Retrograde stem removal in revision hip surgery: removing a loose or broken femoral component with a retrograde nail.

INTRODUCTION: Removal of a cemented femoral stem during revision total hip arthroplasty is a technically demanding procedure that requires a multitude of surgical techniques and tools. To gain full access to the cement and the stem, distal fenestration or a transfemoral approach is often required. This paper presents a technique of retrograde removal of femoral stems and cement from the distal femur. MATERIALS AND METHODS: The authors present five clinical cases. In two cases the femoral component and the surrounding cement was removed using this technique. In the other three cases, due to femoral component fracture, the distal fragment of the femoral component with its cement mantle was removed using the same technique. In an experimental study, we simulated the above technique and compared it with a windowing technique on six, paired cadaveric femora (12 femurs in all). RESULTS: In all of the clinical cases the stem and the cement were removed completely without any complications. The cadaveric experiments clearly showed that the biomechanical resistance of the femur against compression and torsion forces is greatly decreased by using a window to access the proximal femur, compared with the retrograde technique, which shows no significant change. CONCLUSION: Retrograde component removal provides a simple, rapid, and less invasive technique for stem and cement extraction in elective revision hip arthroplasty.