Pediatric Knee and Foot Deformities Lecture

# Pediatric Knee and Foot Deformities ## I. Knee Deformities ### A. GENU VARUM (Bow Legs) Genu varus is an angular leg deformity in which the knees are widely separated while the ankle malleoli are in contact. It may present from infancy through adulthood and has a variety of causes. Infants ma...

# Pediatric Knee and Foot Deformities ## I. Knee Deformities ### A. GENU VARUM (Bow Legs) Genu varus is an angular leg deformity in which the knees are widely separated while the ankle malleoli are in contact. It may present from infancy through adulthood and has a variety of causes. Infants may have physiologic bowing of the legs up to age 2 years, often associated with in toeing. Physiological bowing is symmetrical, involves both femur and tibia and usually resolves spontaneously with the normal growth. Although most cases are physiological, it may be the result of: * vitamin D deficiency * renal osteodystrophy * resistant dietary rickets * osteochondrodysplasia * osteogenesis imperfecta * epiphyseal injury * idiopathic tibia vara (Blount’s disease) ### Risk Factors * Overweight/ Obese infant with early weight bearing. * Improper bed position during sleeping. * Excessive diapering ### Proper Diagnosis Proper diagnosis is essential for proper treatment. **Clinical Examination:** The child is placed in supine with legs extended, the patella facing upward & the medial malleoli approximated. The distance between femoral condyles is measured (intercondylar distance). Also, the distance between the knees at the knee joint line can be used. The deformity may be unilateral with functional limb-length discrepancy or bilateral. ### Treatment Treatment is based on the diagnosis of the cause of the deformity. * **Physiologic genu varum** does not usually require intervention. * **An outer wedge on the shoe** is prescribed for mild cases. * **Deformity that persists after 2 years age** or shows no tendency to correct or is actually worsening; may require bracing in **hip-knee-ankle-foot orthoses (HKAFOs)** or **knee-ankle-foot orthoses (KAFOs)** with no knee joint or a hinged knee joint that can be locked. * **Severe deformity** may need **surgical correction** (leg stapling of the lateral growth plate for teenagers, this allows the unstapled side of the femoral growth plate to continue growing, and the leg gradually grows into better alignment/ osteotomy for older child). ### Conservative physical therapy treatment Includes individualized program consists of stretching exercises for tight muscles and ## B. GENU VALGUM (Knock Knees) Genu valgum is an angular leg deformity in which the ankles are widely separated while the knees are in contract. It is usually associated with severely pronated feet. Asymmetrical genu valgum may result from trauma or fracture of the lateral distal femoral epiphysis. Genu valgus may be the result of: * Congenital fibular hemimelia * Osteochondrodysplasia * Traumatic partial physeal arrest * Osteogenesis imperfect * Growth plate injury due to infection * Contracture of iliotibial band in paralytic conditions (e.g. CP & polio) * Significant femoral anteversion. ### Risk Factors: * Overweight/Obese children. * Flat feet. * Out-toeing foot progression angle. * Awkward gait. ### Clinical Examination: By documenting the intermalleolar distance in supine or standing, with the medial aspects of the knees lightly touching each other. Some adolescents with genu valgum present with anterior knee pain, patellofemoral instability, and difficulty running. ### Treatment depends on the etiological factors. * **Mild cases:** if the distance between the malleoli <3 inches apart, normal development without intervention or conservative treatment usually gives good results. * **Severe cases:** needs surgical intervention (osteotomy) depends on the age of the child and the severity of the deformity. Genu valgum can be safely and effectively corrected in the teenage years by stapling of the medial femoral growth plate. This allows the unstapled side of the femoral growth plate to continue growing, and the leg gradually grows into better alignment. A second option for surgical treatment is femoral osteotomy. ## C. GENU RECURVATUM (Back Knee) It is hyperextension deformity of the knee. The causes may be congenital from the malpositioning in utero, or due to ligamentous hyper-laxity or from bone injury. ### Treatment is based on the etiological factors ### Conservative treatment: * Exercises to regain muscle balance. * Bracing: Back knee support. * Surgical intervention may be needed in severe cases. ## II. Congenital Foot Deformities The infant foot is malleable, making it susceptible to deformation and compression from intrauterine positioning. Alterations in alignment of the foot can be divided into two categories: * **Positional** or **packaging problems** caused by a restricted intrauterine environment. * **True congenital abnormalities** such as talipes equinovarus. ### Foot Deformities include the following: * a.Talipus Equino-varus (Clubfoot) * b.Talipus Equino-valgus * c.Talipus Calcaneo-valgus * d.Talipus Calcaneo-varus * e.Metatarsus Adductus (Hooked Foot) * f.flat foot ## - Talipes Equino-varus (Clubfoot ) Club foot is the most common foot deformity. It is a complex foot deformity involving ankle plantar flexion (equinus), inversion and adduction at the subtalar and midtarsal joints. The condition is bilateral in half the cases. ### Etiology: Is unknown, but it may be due to a combination of environmental and genetic factors. * Intrauterine positioning may be a cause in milder forms (extrinsic clubfoot) or when a primary neuromuscular impairment, such as myelomeningocele or arthrogryposis, is present. * Decreased or absent fetal movement secondary to the primary neuromuscular impairment could lead to prolonged abnormal fetal positioning and the resultant clubfoot deformity at birth. * The etiology may be a defect in the mesenchymal cells forming the template for the cartilaginous model of the hindfoot structures, indicating a dysplasia rather than a deformation. ### Types: * **Structural:** Abnormal bone, joints mal-positioning with severe soft tissues contractures. In the severe forms of congenital TEV (intrinsic clubfoot), pathologic deformities in the anatomy and alignment of the bony structures of the foot are present. * **Non-structural:** mildsoft tissues changes without bone abnormalities ### Physical Examination: * **History** * **Observation:** Shape and size of the feet * Clubfoot is smaller than a normal foot. * Calf is smaller * Hind foot Equinus * Heel in varus * Mid foot is inverted. * Cavus * Abducted big toe. * **Palpation** * **Measurements:** * -ROM and Muscle test. * Functional test: according to the developmental age of the child. ### Treatment for congenital clubfoot: ### Goals of treatment: * To restore alignment and correct the deformity as much as possible and to provide a mobile, plantigrade & painfree foot for normal function and weight bearing. * To increase the strength of foot & lower leg muscles. * To wear normal shoes. * To gain a satisfactory appearance. ### Non- Structural mild deformity Is treated by conservative interventions soon after birth, including: * Mobilizing exercises * Strengthening exercises * Stretching exercises * Electrical stimulation: Faradic stimulation for anterior tibial group. * Splinting: Club foot boot/ Denis Brown night splint. The Ponseti method has demonstrated great success in reducing or eliminating the need for extensive corrective surgery. It consists of the corrective and the maintenance phases. The **corrective phase** includes 4-6 weeks of serial casting with manipulation to correct the forefoot adduction and hindfoot varus followed by percutaneous Achilles tenotomy to correct equinus. **This is followed by the maintenance phase** that includes bracing for 3 months, then nighttime splinting for 2 to 4 years to maintain correction. * Casting should continue until the foot achieves approximately 70 degrees of hyper abduction followed by 3 additional weeks to allow the Achilles tendon to heal. ### Severe structural deformity: needs surgical correction * Surgical correction is usually performed before 6 months of age to limit the extent of secondary deformities from developing. * The surgical procedure is dependent on the age of the child and the severity of the deformity, but typically includes **soft tissue releases** of the tight structures or an anterior tibialis transfer (usually between 3 and 5 years of age) to control dynamic forefoot supination or recurrent deformity. ## B-Talipus Equino-valgus * The deformity consists of ankle plantarflexion, subtalar eversion and midtarsal abduction. * Usually caused due to muscle imbalance as in polio. * Physical examination: includes history, observation, palpation, measurements and functional assessment. * Treatment: conservative/ surgical according to the type, severity of the case and the age of the child. ## B- Talipus Calcaneo-Valgus * Calcaneovalgus is a common positional foot problem in newborns, and more than 30% of neonates have bilateral calcaneovalgus. * The ankle is in excessive dorsiflexion, the forefoot is curved out laterally, and the hindfoot is in valgus. * The dorsum of the foot may actually be touching the anterior surface of the leg at birth. * Physical examination: includes history, observation, palpation, measurements and functional assessment. * Treatment: conservative/ surgical according to the type, severity of the case and the age of the child. * The positional calcaneovalgus foot corrects spontaneously and does not require treatment. * Nonambulators can be treated with shoes that accommodate their deformity, as surgery is considered the only corrective treatment. ## D- Talipus Calcaneo-Varus * The deformity consists of ankle dorsiflexion, subtalar inversion. * Unknown etiology. * Physical examination: includes history, observation, palpation, measurements and functional assessment. * Treatment: conservative/ surgical according to the type, severity of the case and the age of the child. ## - E -Metatarsus Adductus (MTA) * One of the most commonly seen positional conditions in infants. * Adduction of forefoot in relation to midfoot and hindfoot. * The forefoot is curved medially, the hindfoot is in the normal slight valgus position, and full dorsiflexion ROM is noted. * The lateral border of the foot is convex with the curve beginning at the base of the fifth metatarsal resulting in the classic bean shape. * Metatarsus adductus is an example of a deformation caused by intrauterine positioning and is associated with other positional deformations, such as congenital torticollis and DDH. * Observable deformities that have been noted with MTA include: abnormal insertions of the tibialis anterior or posterior tendons, an abnormal shape of the medial cuneiform, and medial obliquity of the 1st cuneiform-1st metatarsal joint. These may be primary causes or adaptive changes. ### Classification of MTA: * Mild (grade I)—clinical correction of the forefoot beyond the midline. * Moderate (grade II)—correction of the forefoot to midline. * Severe (grade III) (metatarsus varus)—forefoot is rigid, and no correction toward midline is possible. * May include medial subluxation of the tarsometatarsal joint. ### Treatment of MTA: * Mild: resolves spontaneously without treatment by 4 to 6 months of age. * Moderate: treated with stretching exercises and corrective shoes (straight- last or reverse-last shoes or both). A recommended stretching technique is to face the child, cup the heel of the foot with the left hand (if right foot MTA), and abduct the foot with the right hand while keeping the heel in varus. Pressure should be applied gently across the metatarsals. * Severe: treated with manipulation and serial casting, followed by corrective shoes until a flexible forefoot with proper alignment is achieved. The height of the serial cast may need to extend above the knee to control any tibial rotation. * Surgery is not considered before 4 years to allow for spontaneous resolution. Although surgery should be used selectively, correction may be important in prevention of further problems as the child reaches adulthood (e.g. metatarsal stress fractures). ## F-F LAT FOOT (Pes Planus) * Flat foot is a common condition seen in the orthopedic clinic, with incidence ranging from 7% to 22%. * The medial longitudinal arch of the foot is not present at birth, and the area of the arch consists of fatty tissue. * Normally, the arch will develop in the first decade of life, with progression of this seen between 2 and 6 years of age. The critical age of development of the arch is 6 years of age, and evaluation before this age may overestimate the problem. * At walking age, an arch may be present in sitting but disappear upon standing, which is referred to as flexible flat foot. Although this condition rarely causes problems, parents are often concerned about the abnormal appearance. * The most common cause of flexible flat foot is ligamentous laxity. Children often will also demonstrate hypermobility of other joints as well, such as fingers, elbows, and knees. In these cases, the child can form an arch when asked to stand on tiptoe. The heels roll into a varus position, and good strength of the ankle and foot muscles is measurable. * Other factors that may influence the prevalence of flat foot are the early wearing of shoes and overweight. * Flat foot can occur secondary to other diagnoses, and these should be considered. A tendo Achillis contracture can produce a secondary flatfoot. ### Treatment of the flexible flat foot generally is not necessary. * Shoe modifications or inserts have been used, although studies have not shown these to be beneficial. * Most pediatric orthopedists who now counsel parents regarding the natural history of improvement in flat feet through childhood advise the use of a lightweight running shoe as the only recommendation. * Using shoes with an arch support and a strong counter will not correct the flat foot but can help decrease wear on the medial border of the shoes. * Some children with flat foot have a rigid, painful foot with limited subtalar motion. Some of these children carry the diagnosis of peroneal spastic flat foot because of clonus in the peroneal muscles, and may be referred for physical therapy. The document also contained two images of the foot, one showing a radiographic x-ray and another showing a diagram of the bones involved in clubfoot.