Hip Arthroscopy and Core Decompression for Avascular Necrosis of the Femoral Head Using a Specific Aiming Guide: A Step-by-Step Surgical Technique

A Comparative Analysis of Osteochondritis Dissecans and Avascular Necrosis: A Comprehensive Review

Musculoskeletal disorders, standing as the fifth leading cause of disability-adjusted life years globally, present significant challenges in orthopedics. Osteochondritis dissecans (OCD) and avascular necrosis (AVN) are distinct but closely related conditions within this spectrum, impacting patients' quality of life with pain, limited mobility, and dysfunction. OCD, involving cartilage and bone detachment in joints, predominantly affects young athletes, but its exact etiology and optimal management remain subjects of ongoing research. Conversely, AVN, marked by bone tissue death due to compromised blood supply, is linked to systemic factors like corticosteroid use and traumatic injuries. Diagnosis for both conditions relies on radiography and magnetic resonance imaging. Conservative treatment for AVN includes the use of a cane or crutches, pharmacological therapy, or physical therapy. On the other hand, in OCD, the primary approach is activity/sports restriction. Surgical treatment options for AVN patients encompass core decompression, bone grafting, or, in the most advanced cases, total hip arthroplasty. OCD may be surgically treated through subchondral drilling or fixation of unstable lesions. Advanced cases of OCD involve cartilage salvage with resurfacing techniques. The presentation of differences between these conditions enhances our understanding, facilitating improved diagnosis and management strategies.

Age is predictive of higher rate of conversion to total hip arthroplasty after core decompression for osteonecrosis of the hip

Background

Core decompression may be performed for early osteonecrosis with a goal of improving symptoms and potentially delaying the need for total hip arthroplasty. The effectiveness and complication rate of this procedure is not well understood given the relatively rare nature of hip osteonecrosis.

Purpose

The purpose of this study is to determine time to total hip arthroplasty (THA) after core compression, assess predictors of early conversion to THA, and to examine complications after hip core decompressions.

Methods

Using Current Procedural Terminology (CPT) codes, we queried the Mariner PearlDiver dataset for patients who underwent hip core decompression. Patient demographics were recorded and subsequent THA conversion within 2 years after surgery were tracked. Patient demographic factors, including age, sex, obesity, diabetes, prior fractures, steroid use, tobacco use, or alcohol use, were evaluated as possible predictors of early conversion to THA. International Classification of Diseases (ICD) codes were used to identify complications at 90 days after core decompression. Multiple linear regression was used to test if the patient demographics significantly predicted conversion to THA and complications after core decompression.

Results

Between 2010 and 2020, 555 patients underwent hip core decompression. Within 2 years of core decompression, 226 patients converted to THA (40.7%). Age was the only significant risk factor for conversion to THA. The highest proportion of patients (61.1%, 138/226) who converted to THA were between age 40-59. The 90-day complication rate was 2.9% (16/555). The most common complication was femoral neck fracture (11/16 of all complications).

Discussion

There is a high failure rate following core decompression for hip osteonecrosis with over one third of patients converting to THA within 2 years. Age was the only variable predictive of conversion to THA. The overall complication rate after core decompression is low at 90 days.

Conclusion

Patients should be counseled regarding the risk of early conversion to THA if over 40 and the potential risk of femoral neck fracture.

Computer-Assisted and Hip Arthroscopy for Avascular Necrosis of the Femoral Head With Femoroacetabular Impingement

Avascular necrosis of the femoral head with femoroacetabular impingement is a disabling disease. Without early treatment and intervention, its further development will even lead to hip osteoarthritis and hip dysfunction. This technical note aims to introduce a computer-assisted precise core decompression of the femoral head, followed by injection of platelet-rich plasma and bone marrow aspirate concentrate. Then, the autologous ipsilateral iliac bone is transplanted to the core decompression area. Thereafter, under hip arthroscopy, the injured glenoid lip of the hip joint is repaired, and the cam deformity of the femoral head/neck junction is polished and formed. The advantages of this technique include accurately locating the core decompression area, combined with autologous cells and bone transplantation, being able to delay the process of avascular necrosis of the femoral head, and evaluating articular cartilage injury, subchondral collapse, and guidance during reaming and curettage.

Rare Bi-focal Presentation of Avascular Necrosis of the Femoral Head: Successful Targeted Treatment as per the Diamond Concept and Review of the Literature

Avascular necrosis of the femoral head (AVNFH) is relatively infrequent, but if undiagnosed or untreated, it may result in significant functional disability, and due to severe ongoing pain, a total hip replacement (THR) may be necessitated. Most cases are associated with trauma, but a number of established risk factors exist. Diagnosis can be challenging but relies on clinical history, physical examination, and radiology. X-ray and MRI are used to stage avascular necrosis (AVN) lesions, which in turn influence management decisions. We present a male in his early 40s, diagnosed with a right-sided AVNFH (Ficat-Arlet stage I) five years previously at another centre. A number of risk factors were identified, such as chronic alcohol abuse, smoking, obesity, and Klinefelter's syndrome. A 'watch and wait' approach was adopted, which included advice on reducing risk factors and commencement on aspirin and alendronic acid. However, his pain had recently increased, resulting in a significant reduction in mobility and an increased reliance on opiates. MRI demonstrated progression to Ficat-Arlet stage II, and the appearance of an additional smaller, second lesion located more medially in the same femoral head. Due to his symptom severity, he was offered a THR. In view of his young age, he came to our tertiary referral centre for a second opinion. He elected for a simultaneous dual surgical decompression of both AVN lesions and biological stimulation for bone-guided regeneration. This involved the delivery of growth factor (bone morphogenetic protein), progenitor cells, and a scaffold/matrix. At 36 months post-operatively, he continued to have the full, pain-free weight-bearing functional capacity, with radiographic imaging demonstrating no residual AVN or femoral head structural collapse. This was a unique case of bi-focal femoral head lesions, treated successfully with decompressions and biological enhancement using the 'diamond concept' for bone repair. In similar situations, when salvage of the femoral head is the preferred treatment option, such a strategy should be considered in the surgeon's armamentarium.

Avascular Necrosis of Femoral Head-Overview and Current State of the Art

Avascular necrosis (AVN) of the femoral head is caused by disruption of the blood supply to the proximal femur. The alterations in the blood supply may occur following a traumatic event or result from a non-traumatic cause. Femoral neck fracture and hip dislocation and associated surgical procedures, corticosteroid therapy, and alcohol abuse frequently lead to AVN development. Type of fracture (displaced or undisplaced) and time between injury and surgery are the most critical factors in assessing the risk of developing AVN. Diagnosis of AVN can be established based on patients’ complaints, medical history, and radiographic findings. There is no consensus on the treatment of patients with AVN to date. Non-surgical methods are dedicated to patients in the early pre-collapse stages of the disease and consist of pharmacotherapy and physiotherapy. Surgery is recommended for patients with advanced disease.