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

Acetabular coverage exerts minimal influence on femoral head collapse and the necessity for surgical intervention in patients with osteonecrosis of femoral head

PURPOSE

The acetabular coverage in osteonecrosis of the femoral head (ONFH) affects the need for surgical intervention, and the collapse of the femoral head remains unclear. This study aimed to evaluate the relation between the acetabular coverage and the need for surgical treatment and femoral head collapse.

METHODS

The study included 158 patients with 252 hips with glucocorticoid administration and idiopathic ONHF without osteoarthritis changes. The mean age at the first visit was 45.2 years, and the mean follow-up period was 92.2 months. All ONFH hips were subsequently divided into two groups: those needing surgical intervention and those without surgery. Additionally, it divided 167 initially non-collapsed hips into those that either later collapsed or not. Radiographic parameters with the centre-edge angle, acetabular roof obliquity, sharp angle, and necrotic location, following the guidelines of the Japanese Investigation Committee, were evaluated.

RESULTS

There were no significant differences in radiographic parameters between the 106 hips that underwent surgery and the 146 hips without surgery. Among the 167 hips without initial collapse, 91 eventually collapsed while 76 did not; their radiographic findings have no significant differences. The necrotic locations were significantly larger in hips requiring surgical intervention or femoral head collapse. Furthermore, 21.8% (55 out of 252 hips) had acetabular dysplasia, which did not significantly correlate with the necessity for surgical treatment or the incidence of femoral head collapse.

CONCLUSIONS

Acetabular coverage has little effect on the necessity for surgical treatment and femoral head collapse in ONFH patients over a long-term follow-up.

Factors related to collapse progression in Japanese Investigation Committee classification type B osteonecrosis of the femoral head

PURPOSE

This study aimed to identify factors related to collapse progression in Japanese Investigation Committee classification type B osteonecrosis of the femoral head (ONFH) and to identify patients who would benefit from surgical treatment.

METHODS

This study included 41 patients (56 hips) with type B ONFH with a minimum follow-up of three years. Based on a ≥ 3 mm collapse progression in ONFH, we categorised patients into two groups: collapse progression and no collapse progression. Sagittal and coronal computed tomography images were used to measure the necrotic region relative to the intact femoral head diameter. The ratios of the necrotic regions of transverse and vertical diameter in coronal and sagittal images are defined as mediolateral transverse and mediolateral vertical, anteroposterior transverse and anteroposterior vertical, respectively. Demographic data and these imaging findings were compared between the two groups. We established a cut-off value for predicting collapse progression through receiver operating characteristic analysis and determined survival rates.

RESULTS

Type B ONFH had a 17.8% collapse progression rate. The mediolateral transverse, mediolateral vertical, anteroposterior transverse, and anteroposterior vertical were significantly higher in the collapse progression group (P < 0.01). Mediolateral transverse was an independent risk factor of collapse progression (hazard ratio, 1.27; 95% confidence interval, 1.03-1.57; P = 0.03), with an optimal cut-off of 45.6%. The 5-year survival rates with collapse progression as the endpoints were 57.0 and 94.9% in the mediolateral transverse of ≥ 45.6 and < 45.6%, respectively.

CONCLUSION

A mediolateral transverse of ≥ 45.6% predicts collapse progression in patients with type B ONFH.

Evaluation of the long-term patient-reported outcomes after hip arthroplasty or joint preserving with Sugioka femoral osteotomy in patients with femoral head osteonecrosis

PURPOSE

This study retrospectively evaluated long-term clinical outcomes and patient-reported outcome measures (PROMs) in patients with osteonecrosis of the femoral head (ONFH) who underwent transtrochanteric rotational osteotomy (TRO), curved varus osteotomy (CVO), and total hip arthroplasty (THA).

METHODS

We retrospectively reviewed the 109 hips in 96 patients (46 men, 50 women) who underwent CVO, TRO, or THA for ONFH treatment. The mean follow-up period for the TRO, CVO, and THA groups was 14.8, 11.5, and 13.3 years, respectively.

RESULTS

The THA conversion rate of the TRO patients was significantly higher than that of the patients with CVO, and the final clinical scores in the patients with TRO did not improve compared with preoperative scores. Postoperative PROMs showed that the total and pain scores of the patients with THA were significantly higher than those of patients with TRO and CVO, while the PROM score did not change between patients with TRO and CVO. The analysis further showed that the preoperative type C2, stage 3A, or postoperative type C1 and C2 were significant predictors of decreased final PROM scores.

CONCLUSION

This study found that CVO and THA are clinically effective treatments for ONFH, with significant improvements compared with preoperative scores. However, THA was associated with significantly higher PROMs and pain scores than those of CVO and TRO in long-term follow-up. Furthermore, our results suggest that postoperative PROMs depend mainly on the preoperative level of collapse and postoperative transposed intact ratio of the articular surface of the femoral head.

Mesenchymal Stem Cell Therapy for Bone Repair of Human Hip Osteonecrosis with Bilateral Match-Control Evaluation: Impact of Tissue Source, Cell Count, Disease Stage, and Volume Size on 908 Hips

We investigated the impact of mesenchymal stem cell (MSC) therapy on treating bilateral human hip osteonecrosis, analyzing 908 cases. This study assesses factors such as tissue source and cell count, comparing core decompression with various cell therapies. This research emphasizes bone repair according to pre-treatment conditions and the specificities of cell therapy in osteonecrosis repair, indicating a potential for improved bone repair strategies in hips without femoral head collapse. This study utilized a single-center retrospective analysis to investigate the efficacy of cellular approaches in the bone repair of osteonecrosis. It examined the impact on bone repair of tissue source (autologous bone marrow concentrate, allogeneic expanded, autologous expanded), cell quantity (from none in core decompression alone to millions in cell therapy), and osteonecrosis stage and volume. Excluding hips with femoral head collapse, it focused on patients who had bilateral hip osteonecrosis, both pre-operative and post-operative MRIs, and a follow-up of over five years. The analysis divided these patients into seven groups based on match control treatment variations in bilateral hip osteonecrosis, primarily investigating the outcomes between core decompression, washing effect, and different tissue sources of MSCs. Younger patients (<30 years) demonstrated significantly better repair volumes, particularly in stage II lesions, than older counterparts. Additionally, bone repair volume increased with the number of implanted MSCs up to 1,000,000, beyond which no additional benefits were observed. No significant difference was observed in repair outcomes between different sources of MSCs (BMAC, allogenic, or expanded cells). The study also highlighted that a 'washing effect' was beneficial, particularly for larger-volume osteonecrosis when combined with core decompression. Partial bone repair was the more frequent event observed, while total bone repair of osteonecrosis was rare. The volume and stage of osteonecrosis, alongside the number of injected cells, significantly affected treatment outcomes. In summary, this study provides comprehensive insights into the effectiveness and variables influencing the use of mesenchymal stem cells in treating human hip osteonecrosis. It emphasizes the potential of cell therapy while acknowledging the complexity and variability of results based on factors such as age, cell count, and disease stage.

The use of extracorporeal shock wave therapy (ESWT) in treating osteonecrosis of the femoral head (AVNFH): a retrospective study

PURPOSE

As most of the cases of avascular necrosis (AVN) in Saudi Arabia is seen in young population and as literature showed good effect of extracorporeal shock wave therapy (ESWT) in reducing pain and oedema in avascular necrosis and delaying the need of surgical intervention. Our purpose of this study is to assess the effectiveness of ESWT in reducing pain, improving range of motion (ROM) and delaying the surgical intervention in patient with AVN of femoral head and compare our results to published literature.

MATERIAL AND METHODS

We have treated 24 patients, 13 males and 11 females with a mean age of 29 years (range 14-48) with 34 hips affected. There were 14 unilateral and ten bilateral lesions. In our series 11 out of 24 patients (45.8%) were due to sickle cell disease. Other causes included idiopathic in five patients (20.8%), corticosteroids use and systemic lupus erythematous in three patients each (12.5% each) and post-traumatic AVN in two patients (8.3%). Extracorporeal shock wave therapy was implanted in FICAT stage I, II and III. All patients had two sessions of extracorporeal shock wave therapy, four to six weeks apart, each with 4000 impulses divided into four points. Radiological and MRI assessment were performed at regular time intervals with a minimum follow-up of two years. Clinical assessment was based on Visual Analog Scale and Harris Hip Score (HHS). The end point outcome measurement was the need for any operative intervention.

RESULTS

Operative intervention was necessary in eight out of 34 hips (23.5%), within an average of 2.5 years (range 1 to 5 years). A hip salvage was achieved in 76.5%. Function was improved with the Harris Hip Score from a mean of 54.6 to 80.4 (P value using paired t test ≤ 0.05). Pain assessed with Visual Analog Scale improved from 5.73 to 2.75 (P value using paired t test ≤ 0.05).

CONCLUSION

We do recommend the use of ESWT in treating AVN of bone whether of femoral head or other sites prior to the collapse of the articular surface. Further studies are needed to compare using two or more sessions as well as using four or six points for ESWT.

Revision hip arthroplasty dislocation risk calculator: when to select dual mobility, large heads, constrained liners, or a standard head size? Testing one hundred thousand hip revisions with artificial intelligence

PURPOSE

Preventing dislocation with large head (≥ 36 mm), dual mobility, or constrained acetabular liner is another option than a standard (≤ 32 mm). Many other dislocations risk factors than size of the femoral head exist after hip arthroplasty revision. Predicting dislocation with a calculator according to the implant, to the indication of revision, and to patient's risks could allow a better surgery decision.

METHODS

Our search method covers the period from 2000 to 2022. A total of 470 relevant citations on hip major revision (cup or stem or both revisions) were identified with artificial intelligence comprising 235 publications of 54,742 standard heads comprising 142 publications of 35,270 large heads, comprising 41 publications of 3945 constrained acetabular components, and 52 publications of 10,424 dual mobility implants. We considered four implant types (standard, large head, dual mobility, or constrained acetabular liner) as the entry layer of the artificial neural network (ANN). Indication for revision THA was the second hidden layer. Demographics, spine surgery, and neurologic disease were the third layer. Implant revision, reconstruction process as next input (hidden layer). Surgery-related factors, and so on. The output was a postoperative dislocation or not.

RESULTS

Of the 104,381 hips that underwent a major revision, a second revision for dislocation was performed for 9234 hips. In each implant group, dislocation remained the first cause of revision. The rate of second revision for dislocation as a percentage of first revision procedures was significantly higher in the standard head group (11.8%) than in the constrained acetabular liner group (4.5%), the dual mobility group (4.1%), and the large head group (6.1%). Instability of a previous THA, infection, or periprosthetic fracture as the indication for revision was increased risk factors as compared with aseptic loosening. One hundred variables were used to create the calculator with the best parameter combination of data and ranking the different factors, according to the four implant types (standard, large head, dual mobility, or constrained acetabular liner).

CONCLUSION

The calculator can be used as a tool to identify patients at risk for dislocation after hip arthroplasty revision and individualize recommendations to select another option than a standard head size.