Knee joint injuries

Hemarthrosis: treatment and complication risks

When blood accumulates in the joint cavity, the primary task is proper immobilization. For this purpose, a cotton-gauze ring or a pneumatic bandage with controlled compression according to L.L. Silin is used. In the very first days, an active regimen for adjacent areas is indicated: isometric contraction of the calf and thigh muscles must be performed, along with movements in the hip joint.

Important: any thermal physiotherapy procedures immediately after the injury are strictly contraindicated, as they can provoke continued intra-articular bleeding.

If a significant volume of blood is not removed (while it is critically important to follow asepsis and antisepsis rules during puncture to prevent infection), severe complications develop. These include the formation of scar-adhesion processes, chronic synovitis, persistent pain syndrome, and limited mobility. The physician must also keep in mind the high probability of concomitant intra-articular injuries.

Meniscal tears: statistics and biomechanics

Meniscal injury is the most common type of trauma in this area. Due to anatomical features and almost complete immobility, the medial meniscus suffers in 80–90% of cases. Tears of the lateral meniscus are significantly less common (10–20%), but it is they that have a greater negative impact on subsequent knee stability.

Clinical practice most frequently encounters an indirect mechanism of injury (for example, during a sudden twist in place, kicking a ball, squat dancing, or falling on the leg):

1. Rotational mechanism (the most common). It occurs with a sudden torso twist when the foot is rigidly fixed and the knee is in a flexed position.
2. Crushing mechanism. Typical for jumping from a height onto straight legs or upon sudden extension from a squatting position.

There is a clear biomechanical pattern: the more flexed the joint is at the moment of trauma, the further posteriorly the tear zone will be located.

Diagnostics and pre-hospital care

At the pre-hospital stage, in the event of joint "locking," immediate immobilization and hospitalization in a trauma unit are required. Any attempts to independently eliminate the "block" are categorically contraindicated, as this leads to further destruction of the meniscus and articular cartilage.

Several methods are used for accurate diagnosis:

• Radiography (in two standard projections). Cartilage tissue itself is radiolucent, so the tear cannot be seen on an X-ray. However, the examination is strictly mandatory to rule out other bone pathology.
• Ultrasound and MRI. Modern non-invasive methods. They clearly demonstrate cystic degeneration (which frequently affects the lateral meniscus due to constant microtraumatization).
• Arthroscopy. The only method that provides absolute (maximum) diagnostic accuracy, unattainable by any radiological studies.

Contrast arthrography and pneumoarthrography are currently almost entirely phased out of practice.

Why surgery is necessary

Delaying treatment is unacceptable. In a sedentary lifestyle, the patient may not notice serious disorders for a long time, experiencing only episodic pain upon exertion and fluid accumulation. An erroneous tactic is treating oneself solely with non-steroidal anti-inflammatory drugs (NSAIDs) and physical therapy, as they provide only a short-term effect.

Without surgery, the damaged meniscus undergoes degeneration and begins to mechanically destroy the articular cartilage. This sustains the pain syndrome, leads to the rapid progression of osteoarthritis, and the development of muscle atrophy and contractures. Absolute rule: once a diagnosis of a tear is established, treatment must be surgical only.

The outdated method of open surgery (arthrotomy with total or partial meniscectomy) is becoming a thing of the past due to high invasiveness, difficulties in complete joint exploration, and the need for prolonged leg unloading (up to 3–4 weeks).

The modern standard is arthroscopy. It allows for "targeted" intervention without damaging viable structures:

• In fresh injuries within the vascular (paracapsular) zone, the tear is secured with sutures or special staples.
• Only non-viable fragments are resected, smoothing the edge.
• Simultaneously, scar tissues, chondroma bodies, and fragments of damaged cartilage are removed.

Following arthroscopic meniscectomy, partial weight-bearing is permitted as early as 3–5 days, and full weight-bearing after 7–10 days. Meniscal endoprosthetics is an actively developing future method.

Stages of conservative rehabilitation

The conservative stage and recovery follow an individualized program designed by a physical and rehabilitation medicine (PRM) physician or exercise therapy specialist.

Immobilization period (home rehabilitation, up to 6 weeks): The leg is fixed with a plaster cast or orthosis strictly in the extended position. The patient moves with additional support on crutches. To improve blood circulation, reduce edema, and prevent muscle atrophy, elevation of the limb, isometric contractions of the thigh and calf muscles, and active movements in the ankle and hip joints are prescribed.

Post-immobilization period (outpatient rehabilitation): The goal of this stage is to restore full weight-bearing capacity and joint function. The program includes:

1. To restore flexion and extension: lightweight dynamic exercises, positioning therapy (postural correction), and exercise therapy in the swimming pool.
2. To normalize muscle tone and blood flow: passive mechanotherapy, pressure therapy, as well as manual leg massage or therapeutic underwater shower massage.

Class and exam questions

What else to study on this topic

• Classification of meniscal injuries according to the N.N. Priorov CITO.
• Peculiarities of blood supply and healing of the paracapsular zone of the meniscus.
• Cystic degeneration of the lateral meniscus against the background of microtraumatization.
• Technique for applying the L.L. Silin pneumatic bandage.
• Prospects and methods of meniscal endoprosthetics.

Other topics in the "Specialized Adult Traumatology" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.