The aim of this study is to assess role of MRI in detecting synovial, cartilaginous , osseous abnormalities ، bleeding inside knee joint and to use a system for assessing HA as support for therapeutic regimes and for monitoring response to therapy .

Hemophilia is a mostly inherited genetic disorder caused by a complete or partial deficiency of coagulation factors VIII or IX, which impairs the body's ability to form blood clots-a process necessary to stop bleeding. This results in prolonged bleeding after injury, easy bruising, and an increased risk of internal bleeding, particularly within joints or the brain.

Hemophilic arthropathy (HA), caused by recurrent hemarthrosis, is the most common musculoskeletal manifestation of hemophilia and one of the most disabling complications of the disease. It can lead to severe pain, deformity, destruction of the joint, debilitating arthritis, and permanent joint damage.

Clinical assessment plays only a minor role in detecting the early stages of HA, as early clinical signs are often nonspecific and of limited value in quantifying disease involvement. Conventional radiographs mainly detect bone lesions that appear in advanced HA, but they cannot identify early changes such as synovial hypertrophy or focal cartilage destruction. Computed tomography (CT) is highly sensitive for detecting bone changes, but it provides limited information on soft tissue involvement and requires a relatively high dose of ionizing radiation.

By contrast, magnetic resonance imaging (MRI) offers superior soft tissue contrast, allowing detailed evaluation of hemophilic joints and visualization of synovial and cartilaginous abnormalities.

T1-weighted imaging: evaluates bone marrow, joint anatomy, and subchondral changes.

T2 fat-suppressed imaging: useful for detecting synovitis and joint effusion.

Gradient echo (GRE) or susceptibility-weighted imaging (SWI): detect chronic blood products (hemosiderin), with SWI being more sensitive and able to identify earlier blood deposits.

Several scoring systems exist for the assessment of hemophilic arthropathy, including the European scoring system and the International Prophylaxis Study Group (IPSG) MRI scale. The IPSG system provides more detailed scoring and greater sensitivity for early disease, including subtle synovial changes. For radiographs, the most widely used system is the Pettersson radiographic scoring system.

In this study, the investigators will use the IPSG MRI scoring system and the Pettersson X-ray scoring system to evaluate hemophilic arthropathy, with the aim of improving grading, management, and follow-up.

Inclusion Criteria:

• Adult patient ( more than 18 years old ) diagnosed as Haemophilia with history of bleeding in knee joint more than once

Exclusion Criteria:

• *contraindications for MRI such as claustrophobia , metallic foriegn body carriers , cardiac pacemaker

  • patient refused the exam
  • Pregnant female patients

The study population will include patients diagnosed with hemophilia A or hemophilia B who are at risk of, or clinically suspected to have, hemophilic arthropathy of the knee joint. Participants will be recruited from hematology and orthopedic clinics.

Eligible participants will undergo knee MRI to assess for:

Synovial abnormalities (e.g., hypertrophy, hemosiderin deposition)

Cartilaginous changes (thinning, erosions)

Osseous changes (subchondral cysts, bone erosions, marrow changes)

Intra-articular bleeding

MRI scoring systems will be applied to quantify disease severity and to evaluate the role of MRI as a tool for supporting therapeutic decisions and monitoring treatment response.