Genu recurvatum is a deformity in the knee joint, so that the knee bends backwards. In this deformity, excessive extension occurs in the tibiofemoral joint. Genu recurvatum is also called knee hyperextension and back knee. This deformity is more common in women and people with familial ligamentous laxity

Ligamentous Laxity

Ligamentous laxity is a term given to describe "loose ligaments."In a 'normal' body, ligaments are naturally tight in such a way that the joints are restricted to 'normal' ranges of motion. This creates normal joint stability...

. Hyperextension of the knee may be mild, moderate, or severe.

Normal range of motion (ROM) of the knee joint is from 0 to 135 degrees in an adult. Full knee extension should be 0 degrees. In genu recurvatum (back knee), normal extension is increased. The development of genu recurvatum, may lead to knee pain

Knee pain

Knee pain is a common complaint for many people. There are several factors that can cause knee pain. Awareness and knowledge of knee pain causes lead to faster diagnosis and treatment. Knee pain can be related to knee joint or around the knee.-Knee joint:...

 and knee osteoarthritis

Knee osteoarthritis

Knee osteoarthritis is a degenerative disease of the knee joint. It is more common in people older than 40 years. Women have greater chance to be affected.-Signs and symptoms:Some of the signs and symptoms associated with knee osteoarthritis include:* Pain...

.

Knee stabilization

The most important factors of knee stability include:

• Ligaments of the knee: The knee joint is stabilized by four main ligaments:
  • Anterior cruciate ligament
    Anterior cruciate ligament
    The anterior cruciate ligament is a cruciate ligament which is one of the four major ligaments of the human knee. In the quadruped stifle , based on its anatomical position, it is referred to as the cranial cruciate ligament.The ACL originates from deep within the notch of the distal femur...
    
     (ACL). The ACL has an important role in stabilization of knee extension movement. This ligament prevents the knee from hyperextending.
  • Posterior cruciate ligament
    Posterior cruciate ligament
    The posterior cruciate ligament is one of the four major ligaments of the knee. It connects the posterior intercondylar area of the tibia to the medial condyle of the femur...
    
     (PCL)
  • Medial collateral ligament
    Medial collateral ligament
    The medial collateral ligament of the knee is one of the four major ligaments of the knee. It is on the medial side of the knee joint in humans and other primates. It is also known as the tibial collateral ligament, or abbreviated as the MCL.- Structure :It is a broad, flat, membranous band,...
    
     (MCL)
  • Lateral collateral ligament (LCL)

• Joint capsule
  Joint capsule
  An articular capsule is an envelope surrounding a synovial joint.-Layers:Each capsule consists of two layers:* an outer layer composed of avascular white fibrous tissue...
  
   or articular capsule (especially posterior knee capsule)

• Quadriceps femoris muscle

• Appropriate alignment of the femur
  Femur
  The femur , or thigh bone, is the most proximal bone of the leg in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in...
  
   and tibia
  Tibia
  The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....
  
   (especially in knee extension position )

Causes

The following factors may be involved in causing this deformity:

• Inherent laxity of the knee ligaments
• Weakness of quadriceps femoris muscle
• Instability of the knee joint due to ligaments and joint capsule injuries
• Inappropriate alignment of the tibia and femur
• Malunion of the bones of around the knee
• Weakness in the hip extensor muscles
• Gastrocnemius muscle
  Gastrocnemius muscle
  In humans, the gastrocnemius muscle is a very powerful superficial pennate muscle that is in the back part of the lower leg. It runs from its two heads just above the knee to the heel, and is involved in standing, walking, running and jumping. Along with the soleus muscle it forms the calf muscle...
  
   weakness (in standing position)
• Upper motor neuron lesion (for example, hemiplegia
  Hemiplegia
  Hemiplegia /he.mə.pliː.dʒiə/ is total paralysis of the arm, leg, and trunk on the same side of the body. Hemiplegia is more severe than hemiparesis, wherein one half of the body has less marked weakness....
  
   the result of a cerebrovascular accident)
• Lower motor neuron lesion (for example, in post-polio syndrome
  Post-polio syndrome
  Post-polio syndrome is a condition that affects approximately 25–50% of people who have previously contracted poliomyelitis—a viral infection of the nervous system—after the initial infection. Typically the symptoms appear 15–30 years after recovery from the original paralytic attack, at an age of...
  
  )
• Deficit in joint proprioception
  Proprioception
  Proprioception , from Latin proprius, meaning "one's own" and perception, is the sense of the relative position of neighbouring parts of the body and strength of effort being employed in movement...
  
  
• lower limb
  Lower limb
  The lower limb is a limb of the body.According to Terminologia Anatomica, it includes the pelvic girdle, buttocks, hip, and thigh, as well as the components distal to the knee.-References:...
  
   length discrepancy
• Congenital genu recurvatum
  Genu recurvatum
  Genu recurvatum is a deformity in the knee joint, so that the knee bends backwards. In this deformity, excessive extension occurs in the tibiofemoral joint. Genu recurvatum is also called knee hyperextension and back knee. This deformity is more common in women and people with familial ligamentous...
  
  
• Cerebral palsy
  Cerebral palsy
  Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
  
  
• Multiple sclerosis
  Multiple sclerosis
  Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...
  
  
• Muscular dystrophy
  Muscular dystrophy
  Muscular dystrophy is a group of muscle diseases that weaken the musculoskeletal system and hamper locomotion. Muscular dystrophies are characterized by progressive skeletal muscle weakness, defects in muscle proteins, and the death of muscle cells and tissue.In the 1860s, descriptions of boys who...
  
  
• Limited dorsiflexion
  Dorsiflexion
  Dorsiflexion is the movement which decreases the angle between the dorsum of the foot and the leg, so that the toes are brought closer to the shin. The movement moving in opposite directions is called plantarflexion...
  
   (plantar flexion contracture)
• Popliteus muscle
  Popliteus muscle
  The popliteus muscle in the leg is used to unlock the knee during walking/running by laterally rotating the femur on the tibia during a closed chain movement ....
  
   weakness
• Connective tissue disorders. In these disorders, there are excessive joint mobility (joint hypermobility) problems. These disorders include:
  • Marfan syndrome
    Marfan syndrome
    Marfan syndrome is a genetic disorder of the connective tissue. People with Marfan's tend to be unusually tall, with long limbs and long, thin fingers....
    
    
  • Ehlers-Danlos syndrome
    Ehlers-Danlos syndrome
    Ehlers–Danlos syndrome is a group of inherited connective tissue disorders, caused by a defect in the synthesis of collagen . The collagen in connective tissue helps tissues to resist deformation...
    
    
  • Benign hypermobile joint syndrome
    Hypermobility
    Hypermobility describes joints that stretch farther than is normal. For example, some hypermobile people can bend their thumbs backwards to their wrists, bend their knee joints backwards, put their leg behind the head or other contortionist performances...
    
    
  • Osteogenesis imperfecta
    Osteogenesis imperfecta
    Osteogenesis imperfecta is a genetic bone disorder. People with OI are born with defective connective tissue, or without the ability to make it, usually because of a deficiency of Type-I collagen...
    
     disease

Treatment

Treatment generally includes the following:

• Sometimes pharmacologic therapy for initial disease treatment
• Physical therapy
  Physical therapy
  Physical therapy , often abbreviated PT, is a health care profession. Physical therapy is concerned with identifying and maximizing quality of life and movement potential within the spheres of promotion, prevention, diagnosis, treatment/intervention,and rehabilitation...
  
  
• Use of appropriate assistive devices such as orthotics
• Surgical treatment

See also

• Genu varum
• Genu valgum
  Genu valgum
  Genu valgum, commonly called "knock-knee", is a condition where the knees angle in and touch one another when the legs are straightened. Women have a wider pelvis than men and a relatively shorter length of the thigh bone, and as a result, have a greater static genu valgum than men...
  
  
• Marfan syndrome
  Marfan syndrome
  Marfan syndrome is a genetic disorder of the connective tissue. People with Marfan's tend to be unusually tall, with long limbs and long, thin fingers....
  
  
• Ehlers-Danlos syndrome
  Ehlers-Danlos syndrome
  Ehlers–Danlos syndrome is a group of inherited connective tissue disorders, caused by a defect in the synthesis of collagen . The collagen in connective tissue helps tissues to resist deformation...
  
  
• Hypermobility
  Hypermobility
  Hypermobility describes joints that stretch farther than is normal. For example, some hypermobile people can bend their thumbs backwards to their wrists, bend their knee joints backwards, put their leg behind the head or other contortionist performances...
  
  
• Osteogenesis imperfecta
  Osteogenesis imperfecta
  Osteogenesis imperfecta is a genetic bone disorder. People with OI are born with defective connective tissue, or without the ability to make it, usually because of a deficiency of Type-I collagen...
  
  
• Knee pain
  Knee pain
  Knee pain is a common complaint for many people. There are several factors that can cause knee pain. Awareness and knowledge of knee pain causes lead to faster diagnosis and treatment. Knee pain can be related to knee joint or around the knee.-Knee joint:...
  
  
• Knee osteoarthritis
  Knee osteoarthritis
  Knee osteoarthritis is a degenerative disease of the knee joint. It is more common in people older than 40 years. Women have greater chance to be affected.-Signs and symptoms:Some of the signs and symptoms associated with knee osteoarthritis include:* Pain...