Definition: Venous cyst or (Hygroma)
Hygroma is a benign cystic formation that arises from the joint capsule or tendon sheath.
About the Condition:
Hygroma represents a fluid-filled formation that can be single or multilocular with minimal association with the main lymphatic system. In Greek translation, “hygroma” means “a tumor containing fluid.”
Cyst formations occur due to injury, leading to local vascular insufficiency in an affected tendon or synovial sheath with disruption of cell bonds in that area. This triggers a cascade mechanism – free radical oxidation, which destructively acts on the connective tissues.
Hygroma (ganglion cyst), according to the International Classification of Soft Tissue Diseases (Enzinger, 1969), is considered a benign process evolving from the joint capsule or tendon sheath. The wall of this cyst consists of extremely tough fibers (the inner layer lined with fibrous cells). The formation can be single or multilocular. Inside the hygroma – a gelatinous content with a yellow color.
Experience shows that hygroma has been detected in more than 60% of people who visited a doctor due to tumor formations. The sizes of hygromas vary greatly and can reach up to 10 cm, but their growth often stops at 2-4 cm. Medical intervention mostly occurs in the wrist joint area, rarely found in the fingers or elbow area, as well as in the foot or knee regions on the leg.
Treatment is determined based on the location and sizes of the hygroma. Two approaches are used – conservative (aspiration of the formation) and surgical (complete removal by traditional method, or laser ablation and other minimally invasive techniques).
Types of Hygroma
The following types of hygroma can be distinguished:
Isolated: Not associated with the joint membrane.
Valvular: The fluid from the hygroma cannot re-enter the joint capsule.
Connected: Communication between the hygroma and the joint capsule is functioning (connected hygroma).
In the latter case, the fluid can periodically exit from the hygroma cavity into the joint capsule but can return to the hygroma cavity later (the “hourglass” phenomenon in joint sliding cases). This creates a false impression of self-healing.
Symptoms
The main symptoms of hygroma include:
Cosmetic discomfort: Presence of a tumor formation.
Discomfort during daily activities at home or work.
Mild to moderate pain: However, pain is absent in about two-thirds of patients.
In most cases, pain occurs when pressing on the hygroma or with its injury. Hygroma rarely compresses blood vessels and nerves, so severe pain may not bother the patient.
How does Hygroma appear?
The skin above the formation appears normal, and the skin color and temperature do not differ from the normal state. Hygroma movement is minimally expressive, and upon touch, slight elastic consistency is noticed (medium between solid and soft elasticity). The close concentration of hygroma to a joint is observed. Joint function near which the hygroma is located is often not affected, but with the growth of the cystic formation, patients may experience discomfort during movement or even pain when attempting joint flexion/extension.
The presence of hygroma on the hand surface (wrist) near the direction of the median nerves or elbow may lead to compression of those nerve fluids, accompanied by moderate pain and numbness in the fingers of the distribution area.
Causes of Hygroma
The formation of the cyst is mostly associated with the sliding of the joint membrane from the joint cavity, which may result from injuries or inflammatory factors, such as joint capsule injuries, arthritis, or synovitis. Thus, the main causes of hygroma are traumatic or inflammatory effects. Under the influence of harmful factors, tendon or synovial sheath tissues receive insufficient oxygen. Local oxygen deficiency leads to the formation of free radicals. These radicals destruct the connective tissues that are poor in antioxidant enzymes. Oxygenation particularly stimulates the function of fibroblasts, which actively begin to divide. As a result, fibroblasts produce a large amount of glycosaminoglycan, which is the main component of the fluid filling the hygroma cavity.
Contributing factors to increasing the risk of hygroma are:
Superficial location of the tendon sheath or synovial sac.
Repetitive actions associated with increased pressure on the joints or tendons.
There are assumptions about a genetic predisposition for hygroma development. For example, in families where one parent suffers from this disease, children often face a similar problem. Sometimes, hygroma can form during pregnancy due to structural changes in connective tissues, which occur due to pregnancy hormones.
Diagnosis:
Clinical recommendations indicate that hygroma diagnosis is based on assessing complaints, objective examination data, and the results of diagnostic imaging techniques.
Ultrasound (Ultrasonography): Allows determining the sizes of the formation, its location, as well as the relationship with large vessels, which is important especially when planning surgical intervention. The advantage of ultrasonography is the ability to determine the leg of the hygroma and image the site of cyst formation.
X-rays: Can identify the features of hygroma and its relationship with surrounding bone structures through X-rays.
Magnetic Resonance Imaging (MRI) or Computed Tomography (CT): Allows to determine more detailed information, essential for differential diagnosis. MRI is considered useful in cases where there are no definitive data from ultrasonography and X-rays. MRI provides the ability to image the connection of the hygroma with the joint cavity.
Treatment
Conservative:
Aspiration with content extraction: A puncture is made for the hygroma with content aspiration.
Aspiration with injection of hormonal or anti-cellular substances: The hygroma is punctured followed by injection of hormonal or anti-cellular substances into its cavity.
Laser cosmetic treatment for hygroma: Laser is used to treat hygroma.
Surgical:
Surgical removal of hygroma: Considered the radical method of hygroma removal.
Sometimes, the use of a tight elastic bandage or immobilization of the joint by a splint is preferred between puncture procedures.
Article Author:
Dr. Ibrahim Mansour
A general practitioner and orthopedic specialist with 9 years of experience in the emergency department. Specializes in treating infectious diseases and gastrointestinal diseases, with a focus on skeletal aspects using therapeutic, surgical, and conservative methods for injuries, including sports-related ones, and major joint diseases in the extremities. His area of interest includes joint-preserving procedures in the knee and hip joints.