Impact of gadolinium-based MRI contrast agent and local anesthetics co-administration on chondrogenic gadolinium uptake and cytotoxicity.

The gadolinium-based contrast agent DOTA-Gd is clinically used in combination with local anesthetics for direct magnetic resonance arthrography. It remains unclear whether gadolinium uptake into cartilage is influenced by co-administration of bupivacaine or ropivacaine and whether DOTA-Gd alters their chondrotoxicity. Gadolinium quantification of chondrogenic spheroids revealed enhanced gadolinium uptake after simultaneous exposure to local anesthetics. Analyses of the spatial gadolinium distribution using synchrotron X-ray-fluorescence scanning indicates gadolinium exposed chondrocytes. In vitro exposure to DOTA-Gd does not alter viability and proliferation of human chondrocytes and the chondrotoxic potential of the anesthetics. Reduced viability induced by ropivacaine was found to be reversible, while exposure to bupivacaine leads to irreversible cell death. Our data suggest that ropivacaine is more tolerable than bupivacaine and that DOTA-Gd exposure does not alter the cytotoxicity of both anesthetics. Enhanced gadolinium uptake into cartilage due to co-administration of anesthetics should find attention.

Pericapsular Nerve Group Block Leads to Small but Consistent Reductions in Pain Between 18 and 24 Hours Postoperatively in Hip Arthroscopy for Femoroacetabular Impingement Surgery: A Prospective, Randomized Controlled Clinical Trial.

PURPOSE: To investigate whether the use of a pericapsular nerve group (PENG) block would reduce perioperative pain after arthroscopic therapy for femoroacetabular impingement syndrome (FAIS) and to examine opioid requirements and occurrence of postoperative nausea and vomiting (PONV). METHODS: Between May 2022 and October 2022, patients (N = 68) undergoing arthroscopic surgery for FAIS were randomly allocated into 2 groups. The first group received an ultrasound-guided PENG preoperatively with 20 mL of 0.375% ropivacaine and standardized postoperative oral medication. The second group received a sham block preoperatively with 20 mL of 0.9% saline and standardized postoperative oral medication. The primary end point was pain scores (visual analog score [VAS], 0-10) during the first 24 hours postoperatively. To quantify clinical significance of outcome achievement for the VAS pain score, the minimal clinically important difference (MCID) was calculated using the half standard deviation method. The incidence of PONV as well as opioid usage (converted to morphine equivalent) within the first 24 hours were secondary outcomes. RESULTS: Randomization and permission were successfully obtained from 68 participants. From the fifteenth postoperative hour, the PENG group reported significantly less postoperative pain than the control group (24th postoperative hour: VAS pain PENG group 1.3 ± 0.9 [0-3]; 95% confidence interval {CI} 0.4-1.2 vs the VAS pain control group 2.4 ± 1.6 [0-5]; 95% CI 1.4-4.7; P = .009). The VAS pain score threshold for achieving the MCID at 24 hours postoperative was defined as a decrease of 1.1. 27 patients (79%) in the PENG group and 22 patients (65%) in the control group were able to achieve MCID (P = .009). Opioid dosage and postoperative nausea did not differ significantly between groups (P = .987 and P = .655, respectively). Concomitant complications such as falls, hematomas, or weakened muscles did not occur in either group. CONCLUSIONS: According to this study, a PENG block minimally reduced pain after arthroscopic treatment for FAIS between the 18th and 24th postoperative hours. The PENG group achieved significantly more often the pain VAS MCID. However, there was no proof that the PENG group consumed fewer opioids than the control group. Overall, PONV was found at a low and comparable rate. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Minced Cartilage Implantation in Acetabular Cartilage Defects: Case Series with 2-Year Results.

OBJECTIVE: The objective was to evaluate clinical outcome and safety of arthroscopic, autologous minced cartilage implantation for acetabular cartilage lesions observed during hip arthroscopy to treat femoroacetabular impingement syndrome (FAIS). DESIGN: Eleven male patients, average age: 29.4 ± 5.4 years, average body mass index (BMI): 24.2 ± 2.2 kg/m2, scheduled for hip arthroscopy due to FAIS accompanied by an acetabular cartilage lesion were included in the case series. Cartilage tissue was harvested and minced from the loose cartilage flap at the chondrolabral lesion by arthroscopic shaver, augmented with autologous conditioned plasma, implanted into the defect, and fixated by autologous thrombin. Concomitant interventions were performed as indicated. The patients were evaluated preoperatively and at 24-month follow-up, using the International Hip Outcome Tool-12 (iHOT-12) and Visual Analog Scale (VAS) pain score and by magnetic resonance imaging (MRI) using the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) grading scale at the 2-year follow-up. RESULTS: The defect size was on average 3.5 cm2 (1.5-4.5 cm2). From preoperatively to 2 years postoperatively, the iHOT-12 significantly improved from 50.2 ± 18 to 86.5 ± 19 (P < 0.0001), and pain score decreased from 5.6 ± 1.8 to 1.0 ± 1.5 (P < 0.0001) on the Visual Analog Scale pain score. Regarding functional outcome and pain, 10 of the 11 patients and all patients reached the minimal clinically important difference (MCID), respectively. The postoperative average MOCART score was 87.2 (± 9.2). No adverse events or reoperations were observed. CONCLUSIONS: Arthroscopic, autologous minced cartilage implantation for treating full-thickness acetabular cartilage lesions in FAIS shows statistically and clinically significant improvement at short-term follow-up.

The Influence of Arthroscopic Shaver Mincing and Platelet-Rich Plasma on Chondrocytes of Intraoperatively Harvested Human Cartilage.

BACKGROUND: Minced cartilage implantation (MCI) has seen a renaissance in recent years. In this evolved technique, human articular cartilage is harvested with an arthroscopic shaver, augmented with platelet-rich plasma (PRP), and implanted with autologous thrombin. This modified technique combines the possibility of cell-based surgical cartilage repair with a minimally invasive autologous 1-step procedure. However, evidence on cell survival and preserved function after shaver-based mincing and PRP supplementation is limited. PURPOSE: To evaluate the effects of arthroscopic shaver mincing and augmentation with PRP on human cartilage tissue. STUDY DESIGN: Controlled laboratory study. METHODS: Standardized samples were taken from 12 donors during autologous MCI. A comparison of cell outgrowth, cell viability, proliferation capacity, and ability to produce extracellular matrix-specific proteoglycans after chondrogenic redifferentiation was made between cartilage taken by curettage from the border of the cartilage defect, cartilage tissue minced by an arthroscopic shaver, and cartilage tissue minced by an arthroscopic shaver that was additionally augmented with autologous PRP. RESULTS: There was no difference between all 3 groups in terms of cell outgrowth or proliferation capacity. Metabolic activity relative to the cell number of chondrocytes isolated from shaver-minced cartilage was higher compared with chondrocytes isolated from cartilage that was derived by curettage or shaver-minced cartilage that was augmented with PRP. After chondrogenic stimulation, the normalized proteoglycan content was higher in spheroids of cells derived from shaver-minced cartilage augmented with PRP than in spheroids of cells derived from curettage. A high correlation of cell outgrowth, proliferation capacity, and viability between isolated cells from all 3 groups taken from an individual donor was observed. CONCLUSION: Chondrocytes isolated from human cartilage tissue that was harvested and minced with an arthroscopic shaver remained viable and proliferative. The augmentation of shaver-minced cartilage with PRP led to the enhanced proteoglycan production of chondrogenic spheroids in vitro, pointing toward the development of a cartilage-specific extracellular matrix. This in vitro study yields promising results regarding the use of an arthroscopic shaver and augmentation with PRP in the context of MCI. CLINICAL RELEVANCE: Knowledge that shaver mincing and augmentation with PRP are feasible for processing articular cartilage during MCI is highly relevant for surgical cartilage repair.

[Minced cartilage procedure for the treatment of acetabular cartilage lesions of the hip joint]. / Das Minced-Cartilage-Verfahren zur Therapie azetabulärer Knorpelschäden am Hüftgelenk.

OBJECTIVE: Treatment of acetabular cartilage defects using autologous cartilage fragments. INDICATIONS: Acetabular cartilage damage (1-6 cm2) associated with femoroacetabular impingement syndrome (FAIS). CONTRAINDICATIONS: Advanced osteoarthritis (≥ 2 according to Tönnis) and extensive acetabular cartilage damage > 6 cm2. Lack of labral containment due to irreparable labral damage. SURGICAL TECHNIQUE: Arthroscopic preparation of the acetabular cartilage damage and removal of unstable cartilage fragments using a 4.0 mm shaver, which minces the cartilage fragments. If necessary, additional cartilage harvesting over the CAM morphology requiring resection. Collection of the cartilage fragments using GraftnetTM and augmentation with autologous conditioned plasma (ACP). Treatment of associated pathologies such as CAM morphology, pincer morphology, and labral refixation or reconstruction. Implantation of cartilage mass and remodeling into the defect zone. Final sealing with autologous fibrin. POSTOPERATIVE MANAGEMENT: Postoperatively, weight bearing is restricted to 20 kg and range of motion to 90° of flexion for 6 weeks. This is supplemented by passive movement using a continuous passive motion (CPM) device. RESULTS: Since 2021, 13 patients treated with the described method were followed up for at least 6 months. A significant increase in the International Hip Outcome Tool (iHot)-12 and a significant reduction of pain were observed. No severe complications occurred.

Combined distal femoral osteotomy and tibial tuberosity distalization is effective in patients presenting with patellar instability and patellofemoral pain due to patella alta and femoral malalignment.

INTRODUCTION: Patellar malalignment has been considered one of the major pathomechanical causes of patellofemoral instability and pain. The results have been reported after femoral varization/torsional osteotomy and tibial tuberosity distalization osteotomy (TTD-O). However, the combination of a femoral deformity (genu valgum/increased femur antetorsion) and patella alta remains underreported. Therefore, the aim of this study was to investigate the clinical outcomes of patients simultaneously treated by distal femoral osteotomy and TTD-O. The hypothesis was that restoration of patellofemoral (PF) alignment via the abovementioned osteotomies would achieve good patient-reported outcome measures. MATERIALS AND METHODS: Between 2016 and 2019, a series of 25 knees in 20 patients were treated by a distal femoral osteotomy combined with a TTD-O aiming to correct patellofemoral malalignment consisting of genu valgum and/or increased femur antetorsion and patella alta. Six patients were lost to follow-up, and one patient refused to participate. Thus, 17 knees in 13 patients (male/female 1/12; age 27.4 ± 5.4 years) were included and comprised the study group for this investigation. Patients were evaluated after a mean of 3.1 ± 0.9 years postoperatively. The Kujala anterior knee pain scale and the PF-subscale of the Knee Osteoarthritis and Outcome score (KOOS-PF) were used to assess patients' reported outcome measures from pre- to postoperatively. RESULTS: The mean amount of torsional correction, valgus correction, and tibial tuberosity distalization averaged 14° (10°-18°), 5.2° (3.8°-8°), and 9 mm (6°-15 mm), respectively. The Kujala score increased by an average of 24.18 points from a mean of 66.6 ± 18.3 points (34-93 points) preoperatively to 90.8 ± 14.2 points (44-100 points) postoperatively (95% CI - 33.0 to - 15.3; p < 0.0001). The KOOS-PF score increased by an average of 33.7 points from a mean of 49.5 ± 24.5 points (9.1-88.6 points) preoperatively to 83.2 ± 21.6 points (15.9 -100 points) postoperatively (95% CI - 47.5 to - 19.9; p < 0.0001). CONCLUSION: The findings of this study indicate that the combination of a distal femoral osteotomy and a tibial tuberosity distalization osteotomy is effective in patients presenting with patellar instability and patellofemoral pain due to patella alta and femoral malalignment.

Revision lateralization osteotomy of the tibial tubercle has excellent outcomes in patients suffering from previous medial tibial tubercle overcorrection.

INTRODUCTION: Tibial tubercle osteotomy (TTO) is a common procedure used to treat patients with patellofemoral instability (PFI) and osteoarthritis (PFOA). Medial patellar maltracking due to previous excessive medialization of the tibial tubercle has rarely been reported. Therefore, the goal of this study was to assess patient-reported outcome measures (PROMs) after revision osteotomy with lateralization of the tibial tubercle (RL-TTO) to correct medial patellofemoral maltracking. MATERIALS AND METHODS: Between 2017 and 2021, a series of 11 patients (male/female 1/10; age 35.8 ± 10.5 years) were treated by RL-TTO, of whom 8 patients could be retrospectively evaluated after a mean of 32.4 ± 15.1 months (range 18-61 months) postoperatively. The Kujala anterior knee pain scale, the patellofemoral subscale of the Knee Osteoarthritis and Outcome Score (KOOS-PF), and a numeric analog scale (NAS; 0-10) regarding anterior knee pain (AKP) at rest and during activity were assessed from pre- to postoperatively. RESULTS: The preoperative mean tibial tubercle-trochlear groove (TT-TG) and tibial tubercle-posterior cruciate ligament (TT-PCL) distances were - 6.5 ± 6.5 mm and 0.7 ± 4.6 mm, respectively. The intraoperatively determined amount of tibial tubercle lateralization averaged 10.7 ± 3.6 mm. The Kujala score and KOOS-PF improved significantly from 33.6 ± 10.1 (23-51) points to 94.4 ± 6.2 points (82-100) (p < 0.001) and from 20.6 ± 13.2 points (0-43.3) to 87.3 ± 9.9 points (72.8-100) (p < 0.001) from pre- to postoperatively, respectively. Pain at rest decreased from 5.8 ± 1.9 to 0.8 ± 0.9 (p < 0.001), and pain during activity decreased from 8.6 ± 1.3 to 1.6 ± 1.5 (p < 0.001). CONCLUSION: RL-TTO significantly improved subjective knee function and AKP in patients suffering from medial patellar maltracking due to previous excessive tibial tubercle medialization osteotomy at short-term follow-up.

Prone Apprehension Relocation Test significantly correlates with radiological instability scores of the hip.

Recently, there was a debate about whether borderline dysplastic hips should be treated surgically with hip arthroscopy or periacetabular osteotomy (PAO). Current studies recommend a classification into stable and unstable hips. Therefore, radiological scores have been described in recent years. Likewise, a new clinical stability test with the Prone Apprehension Relocation Test (PART) has been described. However, there has been no correlation between the modern radiological scores and the PART. We prospectively studied a consecutive group of patients who presented to our clinic. The PART and radiological scores were assessed in these patients. We divided the patients into a PART-positive and a PART-negative group and analyzed the associated clinical and radiological findings. Out of 126 patients (126 hips) included, 36 hips (29%) were evaluated as PART positive. There were significantly more females in the PART positive group (P = 0.005). Comparing the PART groups, significant differences (P < 0.0001) were found for the lateral center edge angle (LCEA), Femoro-Epiphyseal Acetabular Roof (FEAR) index, Gothic arch angle (GAA), anterior wall index (AWI), the occurrence of the upsloping lateral sourcil (ULS) and signs of acetabular retroversion. The correlation analysis showed an association between LCEA, FEAR index, GAA, AWI, ULS and the PART. A chi-square automatic interaction detection algorithm revealed that the strongest predictor of positive PART was the GAA. In conclusion, a high correlation between the PART and known radiological instability parameters was found. Consequently, a combination of clinical instability testing and radiological instability parameters should be applied to detect unstable hips.

Case Report: Intraarticular Iliopsoas Tendon causes Groin Pain Following Periacetabular Osteotomy.

A 43-year-old female patient reported persistent iliopsoas-related groin pain following periacetabular osteotomy (PAO) combined with femoroplasty via a direct anterior approach due to CAM morphology. Concomitantly with the planned removal of screws, hip arthroscopy was performed, and the iliopsoas tendon was found to run intraarticularly, resulting in the tendon being impaired in its mobility and being entrapped. The tendon was arthroscopically released. The patient reported relief of the groin pain after the arthroscopic tendon debridement. During PAO combined with capsulotomy, the postoperatively observed intraarticular position of the iliopsoas tendon should be prevented by careful closure of the joint capsule.

[Minimally invasive periacetabular osteotomy for adult hip dysplasia]. / Minimal-invasive periazetabuläre Osteotomie zur Therapie der Hüftdysplasie des Erwachsenen.

OBJECTIVE: Performance of a periacetabular osteotomy (PAO) using a minimally invasive approach for three-dimensional correction of the acetabular position. INDICATIONS: Symptomatic developmental dysplasia of the hip in adolescents and adults. CONTRAINDICATIONS: Advanced osteoarthritis of the hip, incongruence of the hip joint surfaces. SURGICAL TECHNIQUE: A periacetabular osteotomy is performed via a minimally invasive approach. RESULTS: In total, 39 patients were followed up for 3.5 (3-4.5) years. The lateral center-edge angle of Wiberg increased significantly from 16.1° (7-24°) to 30.5° (25-37°) (p < 0.0001), the acetabular index changed from 13.2° (2-25.3°) to 2.8° (-3-13°; p < 0.0001). Mean duration of surgery was 88 (57-142) minutes. No major complications occurred.