Diz oynagi deformasiyalari

Causes of knee deformities and their treatment

21 March 2022
Dr. Elviz Qasımov

Injuries to the knee joint

The knee joint is one of the body’s most complex joints, and it is also where most of the load is directed. Supporting the weight of our body, the knee joint contributes to the performance of daily movements – walking, running, squatting, going up and down stairs. This is why most patients come in for knee joint complaints. Mostly, injuries and damages to the knee joint can be found in people who participate in sports. Patients who do not exercise and are overweight suffer from patella damage due to muscle weakness and excessive exertion. Friction between the patella and the femur causes serious discomfort. Other causes of knee joint pain include aging (osteoarthritis), congenital deformities, arthritis, trauma, etc.

The knee joint consists of three parts, which are formed by the femur, patella and tibia. Joints are formed between the femur and patella (patellofemoral) and between the femur and tibia (tibiofemoral). All intra-articular surfaces are covered with hard, smooth, slippery cartilage that creates the necessary conditions for movement. The intra-articular fluid helps to nourish and lubricate the cartilage (like in a car engine), thereby promoting comfortable (smooth) movement in the joint. When the intra-articular fluid is normal, the cartilage surfaces of the bone are slippery. Diseases or intra-articular problems that affect the synovial tissue that produces this fluid can change the composition, density, consistency, and amount of fluid, resulting in difficulty and impaired movement in the joint.

The bones that make up the knee joint are flat and do not have congruent surfaces. Cartilage and menisci exist to improve the comparability between the bones. They play a very important role in this process and are located between the femur and tibia. The menisci help spread the load over a larger surface area and distribute it evenly. The ligaments play an important role in stabilizing the knee joint. The knee joint is also supported by the internal and superficial lateral ligaments, the anterior and posterior cruciate ligaments.

Information about knee joint deformities

When the legs are in a normal position, the load on the knee joints is distributed evenly. If the knee joints are curved outward or inward, the load on the knee joints is not distributed evenly, resulting in deformities.

There are two main types of knee joint deformities:

Valgus deformity (genu valqum) is a curvature of the knee joints to the inside, which forms an X-shaped leg and causes additional load on the lateral side of the knee joint. In valgus deformity, the feet are not in contact with each other.

A varus deformity is a curvature of the knee joints to the outside, which creates an “O”-shape of the feet and causes extra stress on the inner (medial) side of the knee joint. With a varus deformity, the patient’s knees are not in contact with each other.

Varus ve valgus deformasiyalari

The figure shows normal, varus, and valgus knee joints


Knee joint deformities can occur for many reasons. Genetic (hereditary) causes are one of the main ones. Genetic incompatibility manifests itself in both joints. The second most common cause of incompatibility in the knee joint is a previous trauma – a fracture of the tibia or damage to the bone growth zone. If previous trauma contributes to the instability, the deformity usually occurs in one knee joint. Because deformities in the knee joint mostly lead to discomfort, patients very often consult a doctor. In addition, they also experience pain symptoms. Patients who suffer from increased stress on one part of the knee joint, as well as with varus and valgus deformities of the knee joints, have an increased risk of developing osteoarthritis.


Conservative treatment usually begins with anti-inflammatory and analgesic medication and physical therapy. In order to reduce the deformity even slightly, you can use a special knee brace. Complete (absolute) cure of knee joint deformity requires surgical interventions.

Surgical treatment is performed for patients over 50 years of age, and is knee joint endoprosthesis. Along with the treatment of osteoarthritis, this method also completely eliminates the deformity. Mature patients who have not developed osteoarthritis undergo osteotomy surgery. An osteotomy surgery procedure is performed to bring the femur for valgus deformity and the tibia for varus deformity of the knee joint into the correct position.

Chondromalacia of the patella

Chondromalacia is the process of gradual softening of the patella surface. This leads to acute pain at the front of the knee. Chondromalacia of the patella is the main cause of chronic knee pain. This condition develops when the juxtaposition between the femur and patella is disrupted. Over time, the cartilaginous surface of the patella becomes thinner due to friction (bending and extending the knee). Thinning of the cartilage in the patella is most common in very young people and patients who play sports. The main factors for this condition are: congenital discrepancy between the femur and patella (patellofemoral); weakness of the muscles (quadriceps muscle); chronic trauma (injuries, bruises, fractures); sports related to running and jumping; various arthritic diseases; overweight.


Injury to the patella is accompanied by pain as well as swelling in some cases. Pain spreads to the front, back, and side surfaces of the knee during: climbing/leaping stairs, prolonged sitting, kneeling, and squatting. Swelling can occur if muscle weakness develops due to pain syndrome.

Examination of the patient

For a patient who goes to the doctor with complaints of knee pain, the doctor performs certain tests during the physical examination and also determines the level of comparability of the patella and femur. Pressure is applied to the patella and the severity of the pain syndrome is assessed. After the physical examination, X-rays and MRI scans are performed for a detailed evaluation of the knee joint.

The classification

There are four degrees of chondromalacia of the patella:

  • First degree – distinguish softening of the cartilaginous surface of the patella.
  • Second degree – abnormal quality of the cartilaginous surface of the patella and soft tissue erosions.
  • Third degree – visible thinning of cartilage and inflammation of soft tissues.
  • The fourth degree is the most severe. Thinning of much of the cartilage results in contact and friction between bony surfaces.
Xondromalaziya patella

The figure shows chondromalacia of the patella

The methods of conservative treatment

The main purpose of conservative treatment is to prevent friction and reduce the load on the patella, by reducing the pressure, you can prevent the cartilage from thinning in the future. As a primary treatment method, the patient is prescribed anti-inflammatory and analgesic medications, an ice pack, and recommended rest. During treatment, the patient should avoid movements that cause pain. To stabilize the knee joint, a kneecap is used. In order to strengthen the quadriceps and hamstring muscles, as well as reduce pain symptoms, the physiotherapist prescribes the patient special physical exercises and conducts certain therapeutic procedures.

Methods of surgical treatment

If conservative treatment is ineffective, arthroscopic surgery is recommended to correct the misalignment between the patella and femur. This surgery involves inserting a camera into the knee joint cavity through one small incision. The problem can be solved by a small intervention. Since most of the discrepancy is in the transition of the patella to the outside, the articular capsule and the external femoral and patellar ligaments are enlarged. In this way, the pressure is reduced and the patellar movement is released. Other surgical interventions are performed to smooth the cartilaginous surfaces of the patella, transplant cartilage tissue and change the attachment site of the thigh muscles.

Ligament damage and rupture

A ligament is a flap of elastic tissue that binds bones together, gives stability to the joint, and strengthens it. There are four main ligaments in the knee joint that perform this function. Knee ligaments bind the femur and tibia together. During injuries to the knee joint, damage to the ligament apparatus can be observed. Muscle weakness, momentary subluxation and twisting of the knee, blows to the knee joint, chronic injuries over the years, and too much exercise can be considered causes of ligament sprains and tears.

The figure shows the four main ligaments of the knee joint

Anterior Cruciate Ligament (ACL) – The ACL and posterior cruciate ligament inside the knee joint cross over each other and form an X shape, thus preventing injury from the front and back of the knee joint. The ACL prevents the tibia from shifting anteriorly. ACL sprains and tears can occur with subluxation, hyperextension, and momentary stoppage during movement. These injuries are mostly seen in people who play soccer, skiing, and basketball.

Symptoms of an ACL injury

  • Sound of a torn ligament in the knee joint, pronounced pain.
  • Swelling in the area of the knee joint and limitation of range of motion.
  • Unstable condition of the joint – occurrence of a feeling of spontaneous dislocation.

Posterior cruciate ligament (PCL) – The PCL is another cruciate ligament that stabilizes the knee joint. It prevents the tibia from moving posteriorly. Damage to the PCL occurs from trauma to the anterior surface of the knee joint, car accidents, and some athletic movements (especially hard falls on a bent knee).

Symptoms of PCL injury

  • Occurrence of pain in the back of the knee joint.
  • Instability of the knee joint.
  • Limitation of range of motion.

Internal Collateral Ligament (MCL – Medial Collateral Ligament) – The MCL is the ligament that supports and stabilizes the knee joint from the inner surface. Any trauma to the joint surface from the outside or momentary bending of the knee, running can cause damage to the MCL.

Symptoms of MCL injury

  • Pain in the knee and its inner surface, swelling and deviation of the knee outward.
  • Sensation at the site of MCL attachment.

Lateral Ligament Lateral Ligament (LCL) – The LCL is the ligament that supports the knee joint on the outside. The main causes of LCL injury are knee subluxation, running, and injuries coming from the inner lateral side.

Symptoms of an LCL injury

  • Pain and swelling in the lateral side of the knee joint.
  • Flexion and direction of the knee joint to the inner side.
  • Sensation in the area of LCL attachment.

Knee ligament sprains are classified according to the degree of damage:

  • First degree (mild) – are seen with microscopic injuries in the ligament and tears. These minor injuries do not have enough impact on the knee joint.
  • Second degree (medium severity) – this degree is characterized by the appearance of partial tears in the ligaments, the patient feels instability in the knee joint when standing and walking.
  • Third degree (severe) – this degree is characterized by complete rupture of the ligaments, separation of them from the bone, the occurrence of instability in the joint.

When a serious injury occurs in one ligament, increases the risk of developing damage in other ligaments. For example, the inner collateral ligament plays a role in maintaining stability and strengthening the joint, and to some extent, it is assisted by the anterior cruciate ligament, so if the MCL is torn, the ACL can be damaged. With moderate to severe damage to the inner lateral ligament, there is a high risk of anterior cruciate ligament rupture.

Examination of the patient

During the examination, the doctor examines the patient and tries to find the cause of the pain. In order to make an accurate diagnosis, the patient is asked specific questions about the movements that cause pain, the presence of sounds in the knee joint, swelling, and instability in the knee joint. During the physical examination, a comparison is made between the injured and healthy knee, and the amount of movement and strength in the joint is checked. A detailed assessment is then performed using diagnostic tests. X-rays and MRI scans are performed.

Methods of treatment

Depending on the degree of ligament damage, conservative and surgical treatment methods are chosen.

Conservative treatment

  • Wearing a kneecap and rest.
  • Application of bandages with ice to reduce swelling.
  • Pain relievers (pills and ointments).
  • Physical therapy and exercises to strengthen muscles.

Surgical treatment

  • For third-degree injuries, i.e., when the ligaments are completely torn, surgical treatment may be recommended.
  • ACL and PCL tears – these tears are treated primarily by arthroscopy, with a flap obtained from the tendon around the knee being inserted in place of the torn ligament.
  • MCL and LCL tears – primary treatment is done with oblique sutures. If three or more weeks have passed since the injury, a graft is taken from the other tendons and reconstruction (repair) of the torn ligament is performed.

Rupture of the patellar tendon

A patellar tendon is a very strong fibrous tissue that attaches a muscle to bone. The patellar tendon starts at the inner surface of the patella and attaches to the tibia. The function of this tendon is to extend the knee.

The figure shows the quadriceps muscle and the patellar tendon

Minor tears and ruptures in the tendon can lead to limitations on walking as well as other physical activities. With a complete rupture, the tendon splits in two, the knee cannot support the weight of the body, and lifting the leg is impossible. In most cases, the patellar tendon rupture occurs at the attachment point to the patella and in rare cases; a piece of bone may come off along with the tendon.

The figure shows a rupture of the patellar tendon

Causes of tendon ruptures

Trauma: serious injuries from falls, jumps, and weight lifting can cause tendon ruptures.

Tendon weakness: the likelihood of a tendon rupture increases with tendon weakness. Several causes can lead to the development of tendon weakness. These include:

Inflammatory tendon disease called patellar tendonitis. This condition is most commonly seen in people who run and jump.

Steroid injections – steroid injections that have been used to relieve inflammation can cause the tendon to weaken.

Chronic diseases like rheumatoid arthritis, chronic renal failure, diabetes mellitus, systemic lupus, etc.

Complications after surgery: operations that were performed around the tendon (endoprosthetics, ligamentous apparatus surgery, etc.). There is a high risk of damage to the tendon.


  • Pain and swelling
  • Increased sensitivity
  • Limitation of physical activity and range of motion (can’t straighten the knee)
  • There is a depression in the area of the tendon rupture

Examination of the patient

During the physical examination, the physician should clarify the time of injury and damage. The physician should ask the patient about previous injuries, patellar tendonitis, and previous surgeries. After the MRI scan, a more accurate diagnosis can be made.

Methods of treatment

Depending on the age of the patient and the severity of the lesion (partial or complete rupture), the appropriate method of treatment is chosen. With a partial tendon rupture, conservative treatment methods are used.

Methods of conservative treatment

Immobilization: In order to immobilize the knee joint, the doctor recommends wearing a kneecap or immobilizer. Within 3 to 6 weeks, you will need a cane (in both hands) along with the immobilizer, and you must not put weight on the knee joint.

Physiotherapy: After the pain and swelling have subsided, you will undergo exercises to strengthen the muscles and therapy in order to restore the range of motion under the supervision of a physiotherapist.

Methods of surgical treatment

During a complete rupture of the tendon, surgical treatment is recommended. Performing surgery immediately after the injury is important. In late applications, muscle shortening and adhesions between tendon fibers can be observed, thus making initial surgery and recovery more difficult. After surgery, a knee brace and supporting orthosis are worn, and within 6 to 8 weeks, weak movements are started. Running is not recommended until the end of the fourth month. At the end of the sixth month, you can return to full-fledged physical activity without restrictions.

Dissecting osteochondritis

Dissecting osteochondritis is a condition that occurs due to idiopathic (unknown) causes, manifested by poor trophic of the cartilaginous part of the bone. This disease can lead to instability of the cartilaginous surface segment, separation of pieces of bone and their free movement in the joint cavity. The bone fragment can contribute to pain and limit range of motion. This condition is most commonly identified in children and adolescents.

In addition to the fact that the cause of dissecting osteochondritis has not been identified, scientists have proven that repeated (chronic) injuries and unbalanced nutrition play a special role in the occurrence of this disease. In addition to these causes, genetic factors, stoppage of blood flow, growth and developmental problems may be considered causes of the disease.

In the knee joint, dissecting osteochondritis occurs most commonly in the patella and femoral condyles, mainly in the medial condyle.

Classification of dissecting osteochondritis

Type I: osteoporosis (bone death) may begin to develop due to impaired bone trophic in a particular area of the knee joint.

Type II: bone death is complete.

Type III: the process of separating part of the cartilage from the bone begins.

Type IV: part of the cartilage completely separates.


Although dissecting osteochondritis can run in a person for many years, it may not show itself. However, pain may occur in the joint if it is moved accidentally or as a result of an injury during sports activities. From the moment the pain occurs, there is swelling and increased sensitivity in the area of the joint. A foreign body, which doctors call a “joint mouse,” can lead to blocked movement in the joint.

Examination methods

The doctor should assess the amount of movement, the presence of swelling, and pain. Radiography and MRI play an important role in the diagnosis of dissecting osteochondritis.

The illustration shows images after radiography and MRI for dissecting osteochondritis

Types of treatment

The choice of treatment depends on the age of the patient and the stage of the disease.

Conservative treatment

Children and adolescents who have completed their growth and development are treated conservatively with immobilization. This treatment consists of limiting the amount of movement, resting, wearing a kneecap, and the patient is also recommended to walk with a cane and crutches.

Surgical treatment

If conservative treatment is ineffective or if pain and blockage of movement due to a “joint mouse” occur, the doctor performs an operative treatment. The type of surgical treatment is chosen depending on the size of the “joint mouse” and the degree of damage. If the diameter of the fragment is less than 2 cm, it can be removed by arthroscopic surgery (closed approach). Fractures with a diameter greater than 2 cm require open surgery. Bone and cartilage grafts are transplanted into the area from which the cartilage has separated, from an area of the joint that is not exposed to stress. This procedure is called mosaicoplasty and performed arthroscopically.

The illustration shows a mosaicoplasty and an image taken during the operation

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