[Modified advanced core decompression (mACD)]

Comparison of the Efficacy of Different Combined Therapies Based on Modified Core Decompression for the Treatment of Early-stage Nontraumatic Osteonecrosis of the Femoral Head: A Retrospective Clinical Study

OBJECTIVE

Osteonecrosis of the femoral head (ONFH) is a severe orthopedic disease, which may cause severe hip dysfunction in later stage. Therefore, it is necessary to treat nontraumatic ONFH during the early stages. The aim of this study was to evaluate the clinical efficacy and survival rates of different combined therapies based on modified core decompression (CD) for early-stage nontraumatic ONFH.

METHODS

This retrospective cohort study assessed 397 hips with ONFH who underwent different combined therapies based on modified CD in our institution between January 2010 and December 2017. Patients were classified into six groups based on treatment modalities, and were followed up at 1 year and 5 years postoperatively. Clinical outcomes, including Harris hip score (HHS) and Western Ontario and McMaster Universities osteoarthritis index (WOMAC), were compared to evaluate the hip function and quick rehabilitation effect. Radiographic progression of ONFH and the incidence of total hip arthroplasty were analyzed to evaluate the survival rate of ONFH postoperatively. Statistical analyses were mainly performed with Kruskal-Wallis test, chi-square test and Kaplan-Meier method.

RESULTS

HHS increased significantly in all groups but showed no significant differences among the six groups in the first years. The nonvascularized allogeneic fibula with bone grafting (NVAF + BG) and percutaneous femoral neck-head fenestration with bone grafting via the direct anterior approach (DAA + BG) groups had significantly higher HHS (p = 0.010; p = 0.025) and WOMAC function score (p < 0.001; p = 0.012) than the CD group 5 years postoperatively. Compared with the CD group, all the other groups showed statistically significant differences in radiographic progression (p < 0.001) and a higher survival rate with no significant difference (p = 0.569).

CONCLUSION

Our study demonstrates the potential use of NVAF + BG and DAA + BG, may serve as a promising combined therapy for the treatment of early-stage nontraumatic ONFH.

Hip Arthroscopy Debridement Combined with Multiple Small-Diameter Fan-Shaped Low-Speed Drilling Decompression in the Treatment of Early and Middle Stage Osteonecrosis of the Femoral Head: 14 Years Follow-Up

OBJECTIVE

Osteonecrosis of the femoral head (ONFH) is a disease that occurs frequently in young and middle-aged people. Because of its high disability rate, it affects the ability to work, so the early treatment of this disease is particularly important. This retrospective study aimed to evaluate the clinical efficacy of hip arthroscopy combined with multiple small-diameter fan-shaped low-speed drilling decompression (MSFLD) in treating early-mid stage ONFH (ARCO II-IIIA) compared to MSFLD, with at least 10-year follow-up.

METHODS

A total of 234 patients who underwent hip arthroscopy and MSFLD for ONFH from 1998 to 2012 were analyzed retrospectively. This study enrolled patients between 18 and 60 years old with ARCO stage II-III A, diagnosed clinically and through imaging, in accordance with the 2021 guidelines for the treatment of ONFH. Clinical data, including demographics, operation mode, BMI, pre- and postoperative Harris score, and femoral head survival rate, were collected. Patients were divided into hip arthroscopy + MSFLD and MSFLD groups based on the operation mode. The t-test was used to compare the postoperative efficacy, Harris scores, and survival rates of the femoral head between the two groups.

RESULTS

Among the 234 patients, 160 cases were followed up, including 92 cases in the hip arthroscopy + MSFLD group and 68 cases in MSFLD group, the follow-up rate was 68.38%, and the follow-up time was (10-22)14.11 ± 3.06 years. The Harris score (80.65 ± 6.29) in the hip arthroscopy + MSFLD group was significantly higher than that in the MSFLD group (p = 0.00), and the survival rate of femoral head (5-year survival rate was 84.78%, 10-year survival rate was 23.91%) was also higher than that in the MSFLD group (5-year survival rate was 63.24%, 10-year survival rate was 8.82%). The 5-year and 10-year survival rates of patients with ARCO II were 82.11% and 28.42%, which were better than 54% and 33% for ARCO III A. The femur head survival rate of alcoholic ONFH (5-year survival rate 61.54%, 10-year survival rate 9.23%) was significantly higher than that of other types of ONFH.

CONCLUSION

Clinical follow-up of at least 10 years suggests that hip arthroscopy combined with MSFLD is an effective treatment for early-mid stage ONFH, with good clinical effect and high survival rate of femoral head.

Optimal drilling at femoral head-neck junction for treatment of the femoral head necrosis: Experimental and numerical evaluation

BACKGROUND

Advanced core decompression (ACD) is a relative new technique for treatment of early stages of avascular femoral head necrosis. Although it is a promising treatment option, there is a need to modify this technique for achieving higher hip survival rates. An idea was to combine this technique with the lightbulb procedure in order to get a complete removal of the necrosis. This study aimed at evaluating the fracture risk of the femora treated by the combined Lightbulb-ACD technique as the basis for clinical application.

METHODS

Subject-specific models were generated from CT scan data of five intact femora. Several treated models were then created from each intact bone and simulated during normal walking activity. Biomechanical testing was additionally performed on 12 pairs of cadaver femora to confirm the simulation results.

FINDINGS

The finite element results revealed that the risk factor of the treated models with a 8 mm-drill increased, but was not significantly greater than that of their corresponding intact models. However, for the femur treated with a 10 mm-drill, the risk factor increased significantly. Fracture always initiated on the femoral neck, i.e. it was either subcapital or transcervical fracture. Our biomechanical testing results correlated well with the simulation data which confirmed the usefulness and effectiveness of the bone models.

INTERPRETATION

The combined Lightbulb-ACD technique using a 10 mm drill increased the fracture risk of femur postoperatively. A drill of up to 8 mm at the anterior head-neck junction did not however lead to the weakening of the femur so that full load bearing may be possible.

Bioactivation of scaffolds in osteonecrosis

Avascular osteonecrosis (AVN) due to local ischemia leads to an inhomogeneous osseous defect, which can be treated by resection and with bone substitute materials in a joint-preserving treatment. Due to the underlying risk profile of AVN, the mostly subchondral localization and the size of the local bone defect, bone regeneration is impaired. Therefore, bioactivation of the applied bone substitute materials prior to application is highly desirable. Apart from the use of growth factors and other soluble substances, the autologous application of location-typical cells and tissue is a useful alternative to support the bone healing properties of scaffolds. This article presents various methods to activate scaffolds for bone stimulation and discusses these techniques with respect to recent data from the literature.

[The importance of removing osteonecrosis during treatment of femoral head osteonecrosis]

Atraumatic femoral head necrosis (aFHN) in adults is estimated to be the leading cause of approximately 10% of all hip prosthesis implantations. Due to the relatively frequent occurrence of aFHN at a young age, the possibility of a joint-preserving intervention should be examined. This includes the classic "core decompression" and modifications based on it. There are different data on the success rates of this method. Reasons for treatment failure could include a lack of clearance of the necrosis zone. The clearance of the necrosis zone is taken into account by alternative surgical procedures for the treatment of aFHN. These are the "trap-door procedure", the "light-bulb procedure" and "advanced core decompression". The current state of knowledge on these procedures is reviewed in this keynote article. It is shown that the extensive excision of femoral head necrosis is of particular importance. None of the procedures mentioned can currently be recommended in preference over the others.

Arthroscopic assessment of concomitant intraarticular pathologies in patients with osteonecrosis of the femoral head

This study's purpose is to arthroscopically assess the occurrence of intraarticular pathologies in patients with osteonecrosis of the femoral head (OFNH) and to compare arthroscopic with radiologic findings. In a retrospective cohort analysis of ONFH patients undergoing combined core decompression (CD) and hip arthroscopy, concomitant intraarticular pathologies were qualitatively and quantitatively assessed by means of arthroscopy. Intraoperative findings were compared with preoperative radiodiagnostics. Descriptive statistics were performed with results displaying type, degree and prevalence of co-pathologies. Based on a cohort of 27 hips with ONFH at ARCO stages II and III, 26 (96.3%) presented with concomitant intraarticular findings. Cam-deformity (n = 22; 81.5%), labral defects (n = 23; 85.2%) and chondral defects (n = 20; 74.1%) were the most frequent. Four hips (14.8%) had foveal ligament anomalies. Intraoperative detection of cam-deformity positively correlated with radiologically assessed pathologic α angles (p = 0.09). Radiologic evaluation of the acetabular labrum distinctly differed from arthroscopic findings. Reliable statements concerning the cartilage status were not possible due to the great difference in quality of the magnetic resonance imaging (MRIs). The results of this study revealed an arthroscopically proven prevalence of co-pathologies in >95% of patients with ONFH. Cam-type deformity, labral anomalies and chondral defects were the most frequent. Comparison of arthroscopic and radiologic findings showed coherent results regarding cam-deformity but revealed distinct difficulties in the assessment of the labral and chondral status emphasizing the need for standardization of preoperative radiodiagnostics. Moreover, it still has to be evaluated whether combined CD and arthroscopy can improve on the overall outcomes achieved by performance of CD only.