Stem cell therapy in bilateral osteonecrosis: computer-assisted surgery versus conventional fluoroscopic technique on the contralateral side

Prognosis of hip osteonecrosis after cell therapy with a calculator and artificial intelligence: ten year collapse-free survival prediction on three thousand and twenty one hips

PURPOSE

Several reports have identified prognostic factors for hip osteonecrosis treated with cell therapy, but no study investigated the accuracy of artificial intelligence method such as machine learning and artificial neural network (ANN) to predict the efficiency of the treatment. We determined the benefit of cell therapy compared with core decompression or natural evolution, and developed machine-learning algorithms for predicting ten year collapse-free survival in hip osteonecrosis treated with cell therapy. Using the best algorithm, we propose a calculator for "prognosis hip osteonecrosis cell therapy (PHOCT)" accessible for clinical use.

METHODS

A total of 3145 patients with 5261 osteonecroses without collapses were included in this study, comprising 1321 (42%) men and 1824 (58%) women, with a median age of 34 (12-62) years. Cell therapy was the treatment for 3021 hips, core decompression alone for 1374 hips, while absence of treatment was the control group of 764 hips. First, logistic regression and binary logistic regression analysis were performed to compare results of the three groups at ten years. Then an artificial neural network model was developed for ten year collapse-free survival after cell therapy. The models' performances were compared. The algorithms were assessed by calibration, and performance, and with c-statistic as measure of discrimination. It ranges from 0.5 to 1.0, with 1.0 being perfect discrimination and 0.5 poor (no better than chance at making a prediction).

RESULTS

Among the 3021 hips with cell therapy, 1964 hips (65%) were collapse-free survival at ten years, versus 453 (33%) among those 1374 treated with core decompression alone, and versus 115 (15%) among 764 hips with natural evolution. We analyzed factors influencing the prediction of collapse-free period with classical statistics and artificial intelligence among hips with cell therapy. After selecting variables, a machine learning algorithm created a prognosis osteonecrosis cell therapy calculator (POCT). This calculator proved to have good accuracy on validation in these series of 3021 hip osteonecroses treated with cell therapy. The algorithm had a c-statistic of 0.871 suggesting good-to-excellent discrimination when all the osteonecroses were mixed. The c-statistics were calculated separately for subpopulations of categorical osteonecroses. It retained good accuracy, but underestimated ten year survival in some subgroups, suggesting that specific calculators could be useful for some subgroups. This study highlights the importance of multimodal evaluation of patient parameters and shows the degree to which the outcome is modified by some decisions that are within a surgeon's control, as the number of cells to aspirate, the choice of injecting in both the osteonecrosis and the healthy bone, the choice between unilateral or bilateral injection, and the possibility to do a repeat injection.

CONCLUSION

Many disease conditions and the heterogeneities of patients are causes of variation of outcome after cell therapy for osteonecrosis. Predicting therapeutic effectiveness with a calculator allows a good discrimination to target patients who are most likely to benefit from this intervention.

Nonoperative and Operative Bone and Cartilage Regeneration and Orthopaedic Biologics of the Hip: An Orthoregeneration Network (ON) Foundation Hip Review

Orthoregeneration is defined as a solution for orthopaedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and, optimally, provide an environment for tissue regeneration. Options include drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electromagnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the hip, including osteonecrosis (aseptic necrosis) involving bone marrow, bone, and cartilage, and chondral injuries involving articular cartilage, synovium, and bone marrow. Promising and established treatment modalities for osteonecrosis include nonweightbearing; pharmacological treatments including low molecular-weight heparin, prostacyclin, statins, bisphosphonates, and denosumab, a receptor activator of nuclear factor-kB ligand inhibitor; extracorporeal shock wave therapy; pulsed electromagnetic fields; core decompression surgery; cellular therapies including bone marrow aspirate comprising mesenchymal stromal cells (MSCs aka mesenchymal stem cells) and bone marrow autologous concentrate, with or without expanded or cultured cells, and possible addition of bone morphogenetic protein-2, vascular endothelial growth factor, and basic fibroblast growth factor; and arterial perfusion of MSCs that may be combined with addition of carriers or scaffolds including autologous MSCs cultured with beta-tricalcium phosphate ceramics associated with a free vascularized fibula. Promising and established treatment modalities for chondral lesions include autologous platelet-rich plasma; hyaluronic acid; MSCs (in expanded or nonexpanded form) derived from bone marrow or other sources such as fat, placenta, umbilical cord blood, synovial membrane, and cartilage; microfracture or microfracture augmented with membrane containing MSCs, collagen, HA, or synthetic polymer; mosaicplasty; 1-stage autologous cartilage translation (ACT) or 2-stage ACT using 3-dimensional spheroids; and autologous cartilage grafting; chondral flap repair, or flap fixation with fibrin glue. Hip pain is catastrophic in young patients, and promising therapies offer an alternative to premature arthroplasty. This may address both physical and psychological components of pain; the goal is to avoid or postpone an artificial joint. LEVEL OF EVIDENCE: Level V, expert opinion.

Robotic-arm assisted THA can achieve precise cup positioning in developmental dysplasia of the hip : a case control study

AIMS

This study aimed to evaluate the accuracy of implant placement with robotic-arm assisted total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH).

METHODS

The study analyzed a consecutive series of 69 patients who underwent robotic-arm assisted THA between September 2018 and December 2019. Of these, 30 patients had DDH and were classified according to the Crowe type. Acetabular component alignment and 3D positions were measured using pre- and postoperative CT data. The absolute differences of cup alignment and 3D position were compared between DDH and non-DDH patients. Moreover, these differences were analyzed in relation to the severity of DDH. The discrepancy of leg length and combined offset compared with contralateral hip were measured.

RESULTS

The mean values of absolute differences (postoperative CT-preoperative plan) were 1.7° (standard deviation (SD) 2.0) (inclination) and 2.5° (SD 2.1°) (anteversion) in DDH patients, and no significant differences were found between non-DDH and DDH patients. The mean absolute differences for 3D cup position were 1.1 mm (SD 1.0) (coronal plane) and 1.2 mm (SD 2.1) (axial plane) in DDH patients, and no significant differences were found between two groups. No significant difference was found either in cup alignment between postoperative CT and navigation record after cup screws or in the severity of DDH. Excellent restoration of leg length and combined offset were achieved in both groups.

CONCLUSION

We demonstrated that robotic-assisted THA may achieve precise cup positioning in DDH patients, and may be useful in those with severe DDH. Cite this article: Bone Joint Res 2021;10(10):629-638.

Mesenchymal stem cell therapy improved outcome of early post-traumatic shoulder osteonecrosis: a prospective randomized clinical study of fifty patients with over ten year follow-up

PURPOSE

Post-traumatic osteonecrosis of the humeral head has a risk of progression to collapse in absence of treatment. The purpose of this study was to evaluate the results of mesenchymal stem cell grafting of the pre-collapse humeral head (study group) in adult patients with osteonecrosis and to compare the results with a simple core decompression without cells (control group). Patients After inclusion and randomization of 50 patients, 26 patients were enrolled in a single-blinded study for the cell therapy group. Twenty-four other patients were treated with simple core decompression without cells (control group).

MATERIAL AND METHODS

After a mean of 12-year (range 10 to 15) follow-up, X-ray and MRI were used to evaluate the radiological results, while the Constant score and the visual analog scale were chosen to assess the clinical results. The cell therapy group was treated with percutaneous mesenchymal cell (MSCs) injection obtained from bone marrow concentration. The average total number of MSCs (counted as the number of colony-forming units-fibroblast) injected in each humeral head was a total injection of average 180,000 ± 35,000 cells (range 74,000 to 460,000).

RESULTS

Both the treatment and control groups had a significantly improved clinical score (p < 0.01). At the last follow-up, pain on the visual analog scale and Constant score in the study group had significant improvement (respectively p < 0.001 and p < 0.01) as compared to the control group. Collapse was observed more frequently in the control group (87.5% versus 11.5% for cell therapy, p < 0.0001). The survival rates based on the requirement for further shoulder surgery (arthroplasty) as an endpoint were higher in the cell therapy group in comparison to those in the control group (92% versus 25%; p < 0.0001).

CONCLUSION

Core decompression with cell therapy was a safe and effective procedure for treatment in the pre-collapse stages of posttraumatic shoulder osteonecrosis and improved the outcome of the disease as compared with simple core decompression without cells.

Efficacy and safety of stem cell therapy for the early-stage osteonecrosis of femoral head: a systematic review and meta-analysis of randomized controlled trials

Background

Osteonecrosis of femoral head (ONFH) is a seriously degenerative disease with no effective therapies to slow its progression. Several studies have reported short-term efficacy of stem cells on early-stage ONFH. However, its long-term effect was still unclear especially on progression events. This study was performed to evaluate the long-term efficacy and safety of stem cells and analyze its optimal age group and cell number.

Methods

Our review was registered on PROSPERO (http://www.crd.york.ac.uk/PROSPERO), registration number CRD42020136094. Following PRISMA guideline, we searched 8 electronic databases on January 5, 2020, and rigorous random controlled trials (RCTs) utilizing stem cell therapy on early-stage ONFH were included. Quality and bias were analyzed. Pooled analysis was performed to assess difference between various outcomes.

Results

A total of 13 RCTs (619 patients with 855 hips) were included. The application of stem cells significantly delayed collapse of femoral head(I², 70%; RR, 0.54; 95% CI, 0.33 to 0.89; P < .00001) and total hip replacement (THR) (I², 68%; RR, 0.55; 95% CI, 0.34 to 0.90; P = .02) in the long term. It effectively decreased the events of collapse of femoral head (≥ 60 months) (I², 0%; RR, 0.37; 95% CI, 0.28 to 0.49; P < .00001) and THR (> 36 months) (I², 0%; RR, 0.32; 95% CI, 0.23 to 0.44; P < .00001). There existed a beneficial effect for patients under 40 (Collapse of femoral head: I², 56%; RR, 0.41; 95% CI, 0.23 to 0.76; P = .004) (THR: I², 0%; RR, 0.31; 95% CI, 0.23 to 0.42; P < .00001). In addition, quantity of stem cells at 10⁸ magnitude had better effects on disease progression events (I², 0%; RR, 0.34; 95%CI, 0.16 to 0.74; P = .007). Besides, there were no significant differences on adverse events between the stem cell group and control group (I², 0%; RR, 0.82; 95% CI, 0.39 to 1.73; P = .60).

Conclusion

Our findings build solid evidence that stem cell therapy could be expected to have a long-term effect on preventing early-stage ONFH patients from progression events, such as collapse of femoral head and total hip replacement. Furthermore, patients under 40 may be an ideal age group and the optimal cell number could be at 10⁸ magnitude for this therapy. Further studies including strict RCTs are required to evaluate a clear effect of stem cells on ideal patient profile and the procedures of implantation.

History of concentrated or expanded mesenchymal stem cells for hip osteonecrosis: is there a target number for osteonecrosis repair?

PURPOSE

Despite multiple possible treatments, the risk of collapse remains the main problem of osteonecrosis. Heart failure (HF). In an effort to address the reverse this issue, curative strategies with regenerative medicine are increasingly being considered. The aim of this technology is to halt or reverse progression of the disease to collapse.

MATERIAL AND METHODS

The pioneering report by Hernigou published in 2002 was the first pilot study suggesting that injection of bone marrow stem cells was a safe approach able to improve osteonecrosis in patients with early stages. Since then, an impressive number of studies and trials employing unselected BM-derived cells (1000 the last 2 years) showed that delivery of those cells to the site of osteonecrosis during core decompression was somehow able to ameliorate the patient with osteonecrosis. In order to translate the promise of this cell therapy into better clinical benefit, many questions need to be addressed. In this review, we therefore analyzed current clinical experience of the literature and our experience of 4000 cases to address these questions and particularly the number of cells that should be injected.

RESULTS

After almost 20 years of clinical research in this field, we are still far from having drawn conclusions on the number of cells we should inject in regenerating hip osteonecrosis. Findings are difficult to interpret due to heterogeneity of causes of osteonecrosis, as well as differences in the cells count, sample quality, and stages of osteonecrosis. The authors address specific issues, as cell quality, cell numbers, volume of osteonecrosis, concentration of cells, and ex vivo expansion. Bone marrow mesenchymal stem cells are supposed to be "functionally competent," but are collected from the bon, marrow of patients with diseases and risk factors of osteonecrosis. The recipient organ (bone osteonecrosis) is a tissue where several alterations have already occurred. These questions are addressed in this review.

CONCLUSION

In this review, we analyzed current clinical experience regarding cell therapy and address issues that should be a guide for future cell-based therapeutic application in osteonecrosis.