Genu recurvatum is a deformity in the
knee joint
In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the h ...
, 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, or ligament laxity, is a cause of chronic body pain characterized by loose ligaments. When this condition affects joints in the entire body, it is called ''generalized joint hypermobility'', which occurs in about ten percent ...
.
Hyperextension of the knee may be mild, moderate or severe.
The normal range of motion (ROM) of the knee joint is from 0 to 135 degrees in an adult. Full knee extension should be no more than 10 degrees. In genu recurvatum, normal extension is increased. The development of genu recurvatum may lead to
knee pain
Knee pain is pain in or around the knee.
The knee joint consists of an articulation between four bones: the femur, tibia, fibula and patella. There are four compartments to the knee. These are the medial and lateral tibiofemoral compartments, the ...
and
knee osteoarthritis
Osteoarthritis (OA) is a type of degenerative joint disease that results from breakdown of joint cartilage and underlying bone which affects 1 in 7 adults in the United States. It is believed to be the fourth leading cause of disability in the w ...
.
Causes

The following factors may be involved in causing this deformity:
* Inherent laxity of the knee ligaments
* Weakness of biceps 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 around the knee
* Weakness in the hip extensor muscles
*
Gastrocnemius muscle
The gastrocnemius muscle (plural ''gastrocnemii'') is a superficial two-headed muscle that is in the back part of the lower leg of humans. It runs from its two heads just above the knee to the heel, a three joint muscle (knee, ankle and subtalar ...
weakness (in standing position)
*
Upper motor neuron lesion
An upper motor neuron lesion (also known as pyramidal insufficiency) Is an injury or abnormality that occurs in the neural pathway above the anterior horn cell of the spinal cord or motor nuclei of the cranial nerves. Conversely, a lower motor ...
(for example,
hemiplegia
Hemiparesis, or unilateral paresis, is weakness of one entire side of the body ('' hemi-'' means "half"). Hemiplegia is, in its most severe form, complete paralysis of half of the body. Hemiparesis and hemiplegia can be caused by different medic ...
as the result of a
cerebrovascular accident
Stroke (also known as a cerebrovascular accident (CVA) or brain attack) is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, d ...
)
*
Lower motor neuron lesion
A lower motor neuron lesion is a lesion which affects nerve fibers traveling from the lower motor neuron(s) in the anterior horn/ anterior grey column of the spinal cord, or in the motor nuclei of the cranial nerves, to the relevant muscle(s).
...
(for example, in
post-polio syndrome)
* Deficit in joint
proprioception
Proprioception ( ), also referred to as kinaesthesia (or kinesthesia), is the sense of self-movement, force, and body position. It is sometimes described as the "sixth sense".
Proprioception is mediated by proprioceptors, mechanosensory neurons ...
*
Lower limb
The human leg, in the general word sense, is the entire lower limb of the human body, including the foot, thigh or sometimes even the hip or gluteal region. However, the definition in human anatomy refers only to the section of the lower limb ...
length discrepancy
* Congenital genu recurvatum
*
Cerebral palsy
Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, spasticity, stiff muscles, Paresis, weak muscles, and tremors. There may be p ...
*
Muscular dystrophy
Muscular dystrophies (MD) are a genetically and clinically heterogeneous group of rare neuromuscular diseases that cause progressive weakness and breakdown of skeletal muscles over time. The disorders differ as to which muscles are primarily af ...
* Limited
dorsiflexion
Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relativ ...
(
plantar flexion contracture)
*
Popliteus muscle
The popliteus muscle in the leg is used for unlocking the knees when walking, by laterally rotating the femur on the tibia during the closed chain portion of the gait cycle (one with the foot in contact with the ground). In open chain movements ...
weakness
* Connective tissue disorders. In these disorders, there are excessive joint mobility (joint hypermobility) problems. These disorders include:
**
Marfan syndrome
Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with long arms, legs, fingers, and toes. They also typically have exceptionally flexible joints a ...
**
Loeys–Dietz syndrome
Loeys–Dietz syndrome (LDS) is an autosomal dominant genetic connective tissue disorder. It has features similar to Marfan syndrome and Ehlers–Danlos syndrome. The disorder is marked by aneurysms in the aorta, often in children, and the aort ...
**
Ehlers–Danlos syndrome
**
Benign hypermobile joint syndrome
**
Osteogenesis imperfecta
Osteogenesis imperfecta (; OI), colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that break easily. The range of symptoms—on the skeleton as well as on the body's other organs—may b ...
disease
Pathophysiology
The most important factors of knee stability include:
*
Ligaments
A ligament is the fibrous connective tissue that connects bones to other bones. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Other ligaments in the body include the:
* Peritoneal ...
of the knee: The knee joint is stabilized by four main ligaments:
**
Anterior cruciate ligament
The anterior cruciate ligament (ACL) is one of a pair of cruciate ligaments (the other being the posterior cruciate ligament) in the human knee. The two ligaments are also called "cruciform" ligaments, as they are arranged in a crossed formation ...
(ACL). The ACL has an important role in stabilization of knee extension movement by preventing the knee from hyperextending.
**
Posterior cruciate ligament
The posterior cruciate ligament (PCL) is a ligament in each knee of humans and various other animals. It works as a counterpart to the anterior cruciate ligament (ACL). It connects the posterior intercondylar area of the tibia to the medial con ...
(PCL)
**
Medial collateral ligament
The medial collateral ligament (MCL), or tibial collateral ligament (TCL), is one of the four major ligaments of the knee. It is on the medial (inner) side of the knee joint in humans and other primates. Its primary function is to resist outwar ...
(MCL)
**
Lateral collateral ligament (LCL)
*
Joint capsule
In anatomy, a joint capsule or articular capsule is an envelope surrounding a synovial joint.Quadriceps femoris muscle
The quadriceps femoris muscle (, also called the quadriceps extensor, quadriceps or quads) is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the sole extensor muscle of the knee, forming a large ...
* Appropriate alignment of the
femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates wit ...
and
tibia
The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...
(especially in knee extension position )
Incidence
This condition is considered to be rare, with about 1 in 100,000 births being affected by the congenital form of genu recurvatum, although it's a common feature in some disorders, such as in joint hypermobility, which affects 1 in 30 people.
Treatment
Treatment generally includes the following:
* Sometimes pharmacologic therapy for initial disease treatment
*
Physical therapy
Physical therapy (PT), also known as physiotherapy, is one of the allied health professions. It is provided by physical therapists who promote, maintain, or restore health through physical examination, diagnosis, management, prognosis, patie ...
: physiotherapy will be beneficial in patient with complaint of pain, discomfort.
*
Occupational therapy
Occupational therapy (OT) is a global healthcare profession. It involves the use of assessment and intervention to develop, recover, or maintain the meaningful activities, or ''occupations'', of individuals, groups, or communities. The field o ...
* Use of appropriate assistive devices such as orthoses
* Surgery
See also
*
Genu varum
Genu varum (also called bow-leggedness, bandiness, bandy-leg, and tibia vara) is a varus deformity marked by (outward) bowing at the knee, which means that the lower leg is angled inward ( medially) in relation to the thigh's axis, giving ...
*
Genu valgum Genu, a Latin word for "knee," may refer to:
* Genu of internal capsule
* Genu of the corpus callosum
* Genu recurvatum
* Genu valgum
* Genu varum
Genu varum (also called bow-leggedness, bandiness, bandy-leg, and tibia vara) is a varus def ...
*
Hypermobility
References
External links
The American Academy of Orthotists and ProsthetistsThe differential diagnosis of children with joint hypermobility: a review of the literatureThe American Academy of Orthotists and Prosthetists
{{Congenital malformations and deformations of musculoskeletal system
Musculoskeletal disorders
Rheumatology
Orthopedic problems
Knee injuries and disorders
Rare diseases