AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Blount disease is an uncommon growth disorder characterized by disordered ossification of the medial aspect of the proximal tibial physis, epiphysis, and metaphysis. This progressive deformity is manifested by varus angulation and internal rotation of the tibia in the proximal metaphyseal region immediately below the knee. The natural history of this disease leads to irreversible pathologic changes, especially at the medial portion of the proximal tibial epiphysis because of growth disturbances of the subjacent physis.¹
 

A 10-year-old boy with Blount disease. Marked obesity and bilateral genu varum is present. Courtesy of S. Standard, MD.



Diagram depicting the radiographic changes observed in the infantile form of Blount disease and their development with increasing age.


Blount disease can occur in growing children of any age and is classified into 2 groups: early onset and late onset. Early onset (in children <3 y) is termed the infantile type. The late-onset group includes the juvenile form (in children aged 4-10 y) and adolescent form (in those aged 11 years and older) of the disease. Juvenile tibia vara usually is discussed with the infantile type, and the remainder of this article addresses infantile and juvenile types as part of the broader grouping of the infantile type.^{2, 3, 4}

In 1922, Erlacher described the first case of tibia vara. However, Blount's article in 1937 prompted the recognition of this disorder. Blount presented a series of 13 new cases and reviewed the 15 cases in the literature.⁵ He delineated the similarities between infantile and adolescent tibia vara and emphasized the differences in their etiology. Because he was the first to identify the similar clinical, radiographic, and pathologic characteristics of the cases in the literature, the disease has become associated with Blount. ⁶

Tibia vara and osteochondrosis deformans tibiae are two other terms that have been used to describe the deformity of Blount disease. Blount suggested the anatomic term tibia vara, which is the generally accepted term.⁵ However, the term does not identify the specific location of the abnormality, nor does it indicate the etiology of the disease. The term osteochondrosis deformans tibiae is not accurate because it describes a disorder in which the primary or secondary centers of ossification undergo avascular necrosis.⁶ Avascular necrosis has never been found in either form of Blount disease.⁷ Hence, Blount disease and tibia vara continue to be the most commonly accepted terms for the disease.


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Specialty site Orthopaedics
Orthopaedics News

Related eMedicine topic:
Tibial Bowing
Tibial Torsion

Problem

Disordered growth of the proximal medial physis, epiphysis, and metaphysis of the tibia results in a progressive varus deformity below the knee.

Frequency

The estimated prevalence of infantile Blount disease in the population of young children with significant bowlegs in the United States is 0.007, or less than 1%; the prevalence of adolescent Blount disease may reach 2.5% in the population at greatest risk (see image below).^{8, 9} The exact frequency in persons of all ethnicities is unknown and most likely is less than 1%. In addition to race and body weight, the frequency is increased if other family members have been diagnosed as having Blount disease.^{10, 11}



A 10-year-old boy with Blount disease. Marked obesity and bilateral genu varum is present. Courtesy of S. Standard, MD.

Etiology

The cause of Blount disease remains controversial, but it is most likely secondary to a combination of hereditary and developmental factors. Biomechanical overload of the proximal tibial physis due to static varus alignment and excessive body weight have been implicated in the etiology of infantile tibia vara. The compressive forces at the medial aspect of the knee appear to cause growth suppression. Although similar processes may be implicated in the development of adolescent tibia vara, static varus alignment is not a prerequisite.¹² Dynamic gait variation secondary to increased thigh girth has been suggested to be implicated in the development of adolescent Blount disease.¹²

A number of authors have noted a positive family history of Blount disease in some affected individuals. Data supporting inheritance are limited but worthy of mention. Sevastikoglou and Eriksson based this contention on the finding of 4 persons with tibia vara in the same family, of whom 2 were identical twins.¹¹ Schoenecker et al also found a positive family history in 14 of 33 patients.¹⁰ However, no direct proof of a genetic relationship has been discovered.

Pathophysiology

Blount disease most likely is caused by a combination of excessive compressive forces on the proximal medial metaphysis of the tibia and altered endochondral bone formation.^{5, 13, 14} It is unclear whether the deformity is caused by an intrinsic alteration of bone formation that is exacerbated by compressive forces or by compressive forces that cause a disruption in normal endochondral bone formation.

Weight bearing must be necessary, since the disease does not occur in nonambulatory patients.¹⁵ Cook et al correlated epidemiologic and histologic findings in a model that provided evidence for the role of biomechanical overload in the pathogenesis of infantile tibia vara. They analyzed static single-limb stance in children and determined that 10° and 20° varus deformities, in children aged 2 years and 5 years, respectively, could generate compressive forces adequate to retard growth of the medial tibial physis.¹⁵

The combination of mechanical and biologic factors in tibia vara most likely impacts the disease to varying extents. Furthermore, excessive physiologic bowing often is found in individuals with the infantile form of the disease. It is known that epiphyseal compression inhibits physeal growth (the Heuter-Volkmann law) and distraction stimulates growth.¹⁶ Delpech demonstrated this stimulation by showing that release of abnormal pressure from a physis causes increased vertical growth.¹⁶ Such compressive forces cause a relative inhibition of growth of the medial portion of the proximal tibial physis, as compared with the lateral portion.

It is also known that damaged cartilage ossifies more slowly.¹⁷ Histologic sections of cartilage in the infantile form show damaged cartilage. If the cartilage on the medial aspect of the plateau is damaged, ossification is delayed on the medial side of the tibia compared with the lateral side. The result is a progressive varus angulation below the knee and an increase in the compressive forces on the physis, which changes the direction of the weightbearing forces on the upper tibial epiphysis from perpendicular to oblique. The obliquity of this force tends to displace the tibial epiphysis laterally. The trabecular pattern of the metaphyseal region in the tibia curves medially to align itself to the deviation of the stress.¹⁸

Many authors believe that disease progression is the result of this cycle of growth disturbance, varus deformity, and further growth disturbance.^{7, 13} Distal femoral valgus or varus deformity and/or distal tibial varus or valgus deformities also can occur in conjunction with tibia vara.¹⁹ Whether these occur as compensatory mechanisms or are due to intrinsic factors of Blount disease is unknown. These deformities should be corrected at the same time the tibial vara deformity is corrected.

Histologic specimens from the medial tibial condyle in the infantile form of the disease show changes principally in the zone of resting cartilage in the proximal tibial physis. These changes consist of (1) islands of densely packed cells that exhibit a greater degree of hypertrophy than would be expected from their topographical location, (2) islands of almost acellular fibrous cartilage, and (3) abnormal groups of capillary vessels. ¹³

The pathogenesis of the adolescent form of the disease remains less clear than that of the infantile form. Some authors consider the 2 forms to have similar pathophysiology, while other authors consider them to be separate entities. Adolescent Blount disease does not appear to be as progressive or as common as the infantile form. Factors such as injury or infection of the physis have been suspected to play an etiologic role; however, most patients have no history of trauma or infection, leading many authors to discount them as the only possible causes.^{5, 7, 20, 21}

Clinical

The clinical presentation of the different types of tibia vara varies according to the age of onset. In infantile tibia vara, children generally start to walk early, usually when aged 9-10 months.¹³ At the onset of the disease, differentiating between early infantile Blount disease and marked physiologic bowlegs is difficult.

Physiologic genu varum is a common torsional deformity that occurs secondary to normal in utero positioning. The tight posterior hip capsule causes an external rotation of the thigh at the hip. When combined with internal tibial torsion, the resulting appearance is a varus deformity. This physiologic deformity usually resolves spontaneously by the time the child is aged 2 years. In contrast to physiologic genu varum, infantile Blount disease can progress to severe deformity.

The infantile form is generally more prevalent in females, blacks, and those with marked obesity. It is associated with a prominent metaphyseal beak, internal tibial torsion, and leg-length discrepancy; involvement is bilateral in approximately 80% of cases.¹⁸ The metaphyseal prominence, or beak, may be palpable over the medial aspect of the proximal tibial condyle. Patients usually do not complain of pain. However, the deformity of the lower extremity can be quite pronounced.^{5, 6, 10}

In contrast, patients with adolescent tibia vara usually complain of pain at the medial aspect of the knee. These patients are typically overweight or obese. In contrast to infantile tibia vara, involvement is unilateral in 80% of cases; the involved leg sometimes is shorter than the opposite leg by as much as 2-3 cm. The degree of varus deformity usually is not as severe as in individuals with the infantile form and usually does not exceed 20°.¹⁸

INDICATIONS

Section 3 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Indications for operative treatment include increasing severity of symptoms or progression of deformity.

RELEVANT ANATOMY

Section 4 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

For direct exposure for osteotomies on the medial aspect of the knee or pin fixations, surgeons must be aware of the location of the infrapatellar branch of the saphenous nerve. On the lateral side, it is the course of the peroneal nerve around the fibula that deserves attention. One must be aware that lengthening or shortening procedures can cause injury to the anterior tibial artery. Avoidance of injury to the neurovascular structures is paramount in obtaining a good result.

Osteotomies in the epiphyseal or metaphyseal region of the proximal knee must necessarily avoid the epiphyseal plate in the growing child to prevent premature closure. It is important to remember that the epiphyseal plate is often "V" shaped, with the apex pointing inferiorly in the proximal tibia and superiorly in the tibia.

CONTRAINDICATIONS

Section 5 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Surgical intervention is contraindicated in children who are younger than 2 years because it is difficult at this age to differentiate between Blount disease and excessive physiologic bowing that may resolve spontaneously. In patients with adolescent Blount disease, surgical intervention is recommended only when the patient complains of pain associated with the deformity.

WORKUP

Section 6 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Lab Studies

• Lab studies have not been shown to aid in the diagnosis of Blount disease. The diagnosis of both forms of Blount disease is based on history, physical examination, and, most important, radiographs of the knee.

Imaging Studies

Anteroposterior radiograph of the knee demonstrating the medial plateau depression and prominent metaphyseal beaking (Langenskiöld stage II-III) typical of infantile genu varum regardless of age of presentation.



Anteroposterior radiograph representing important angles for staging typical for the adolescent form. Obvious varus deformity in the proximal tibia with no sloping or bar formation is present (bars do not occur in the adolescent form). A: Tibiofemoral angle. B: Metaphyseal-diaphyseal angle. C: Metaphyseal-epiphyseal angle.

• Radiographs of the knee are critical in assessing and staging the severity of the deformity. An anteroposterior standing radiograph of both lower extremities and a lateral radiograph of the involved extremity are used (see the top image above).
• • Fragmentation with a protuberant step deformity and beaking of the proximal medial tibial metaphysis are the major features of the infantile group. The lateral cortical wall of the upper tibial metaphysis is nearly straight.
  • Differentiating between severe physiologic bowing and infantile-type Blount disease is difficult in early childhood. Thus, corrective intervention is not recommended when the patient is younger than 2 years.
  • Early changes of infantile Blount disease can be assessed by measuring the metaphyseal-diaphyseal angle of the proximal tibia; that is, the angle formed by the intersection of a line through the transverse plane of the proximal tibial metaphysis with a line perpendicular to the long axis of the tibial diaphysis (see the lower image above).
  • The severity of the varus deformity is based on the tibiofemoral angle as measured on standing anteroposterior radiographs that include the ankle, knee, and most of the femur; the metaphyseal-diaphyseal angle; and the metaphyseal-epiphyseal angle, that is, the angle formed by the intersection of a line through the transverse plane of the proximal tibia epiphysis with a line through the transverse plane of the metaphysis (see the lower image above).

Histologic Findings

In the infantile form, bone changes include delayed ossification of the medial epiphysis and metaphysis of the proximal tibia.⁶ In all stages of the disease, histologic specimens from the zone of resting cartilage in the medial part of the proximal tibial physis have well-defined pathologic changes, as described in Pathophysiology. These consist of (1) islands of densely packed cells exhibiting more hypertrophy than expected on the basis of their position in the growth plate, (2) islands of fibrocartilage that are nearly acellular, and (3) abnormal groups of capillary vessels. No avascular necrosis of bone or inflammation has been demonstrated.^{5, 13, 18, 21}

Staging

Langenskiöld classified infantile tibia vara into 6 progressive stages, based on the degree of metaphyseal-epiphyseal changes observed on the radiograph. Severity of disease is based on the Langenskiöld stage and the age of the child.^{17, 21, 22}

Anteroposterior radiograph representing important angles for staging typical for the adolescent form. Obvious varus deformity in the proximal tibia with no sloping or bar formation is present (bars do not occur in the adolescent form). A: Tibiofemoral angle. B: Metaphyseal-diaphyseal angle. C: Metaphyseal-epiphyseal angle.

TREATMENT

Section 7 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Medical therapy

Treatment depends on the age of the child and the severity of the varus deformity.
 
Observation or a trial of bracing is used most frequently for children aged 2-5 years. However, progressive deformity usually requires osteotomy.^{7, 10} Operative treatment is not recommended for children younger than 2 years because the deformity may be an exaggerated physiologic genu varum.

Nonoperative treatment

In a child older than 2 years, orthotic treatment can be used when the deformity is increasing or if the child has a tibiofemoral angle greater than 15°, a metaphyseal-diaphyseal angle of greater than 11°,²³ and a metaphyseal-epiphyseal angle of 25-30°.¹⁸ Ambulatory daytime bracing using an above-the-knee brace with a free ankle may favorably alter the natural history of patients with tibia vara who are younger than 3 years and who have Langenskiöld stage I or II deformity, because the deformity is often reversible at these stages.²⁴

Nonetheless, documentation of the effectiveness of bracing is difficult because tibia vara can resolve spontaneously. 

If the deformity persists or increases to stage III or IV with daytime brace treatment, osteotomy is required. If possible, it is preferable to perform the osteotomy before the child is aged 4 years to prevent recurrence.²⁵ If deformity is severe (ie, Langenskiöld stage V or VI), operative correction is essential. Orthotic devices are ineffective in controlling the varus deformity in adolescents, and the treatment is surgical.

Related eMedicine topic:
Lower Limb Orthotics

Surgical therapy

Surgical approaches for infantile Blount disease

If the deformity does not improve with orthotic treatment and the disease progresses radiographically to advanced stage II or stage III deformity, surgical correction should be performed. Furthermore, surgery is recommended for a deformity that is increasing in severity and disabling the child, or if the child has a tibiofemoral angle greater than 15°, a metaphyseal-diaphyseal angle greater than 14°, and a metaphyseal-epiphyseal angle greater than 30°. Absolute indications for surgery are depression of the tibial plateau, impending closure of the medial physis of the upper tibia (stage IV), and ligamentous laxity of the knee.¹⁸

Osteotomy has been the most frequently used form of surgical management.⁶ Many different types of osteotomies have been described in the literature, including opening and closing wedge, spike, dome, and oblique osteotomies.^{22, 26, 27} In the more skeletally mature individual, the valgus osteotomy can be carried out through the physeal scar. However, it is important to remember that in the younger child, the osteotomy must be carried out below the insertion of the patellar ligament because the proximal tibia physis is still open.⁷

The rate of recurrence of the varus deformity is high in individuals with infantile Blount disease treated with proximal tibial and fibular osteotomy.^{5, 10, 17} Doyle et al identified only 2 prognostic features for the recurrence of deformity: the patient's age and Langenskiöld stage at initial osteotomy.²⁵ They recommended (1) operative treatment before age 4 years for patients with progressive clinical and radiographic findings; (2) surgical correction when radiographic findings correspond to Langenskiöld stage I or II; and (3) a single corrective osteotomy early on the affected limb that results in permanent correction. The failure to correct the tibia vara deformity early can result in permanent physeal damage, with development of symptomatic degenerative intra-articular knee pathology at maturity.

Surgical approaches for adolescent Blount disease

In individuals with adolescent tibia vara, observation is indicated when the deformity is not progressing, not causing severe deformity, and not disabling the patient, because spontaneous regression has been reported.^{5, 17} Surgical treatment depends on the stage of the disease and the skeletal age of the child. Many surgical procedures have been described for treating adolescent tibia vara with disease progression, including proximal tibial osteotomy, hemiepiphysiodesis, asymmetric physeal extraction, and external fixation with distraction osteogenesis.^{9, 20, 28, 29, 30, 31}

As in the infantile form, osteotomy remains the most common method of treatment.⁶ If adolescent tibia vara is recognized early with a physeal bony bridge and minimal deformity, then it may be excised and spacer material, such as fat, inserted. When disease is moderate to severe, a more extensive procedure is indicated. For girls older than 11-12 years or for boys older than 13-14 years, remaining growth is minimal, and physeal bony bridge resection is meaningless.¹⁸

A second option is osteotomy through the growth plate to elevate the medial epiphysis, and a contralateral epiphysiodesis. This approach relies on the growth of the injured medial physis, and results have been unpredictable, with up to 40% of patients requiring additional surgery to improve alignment.⁹

The third option is proximal tibial osteotomy below the physis so that the tibia is realigned mechanically. This option requires the presence of spontaneous bridging and early closure of the medial part of the proximal tibial physis, an opening of the lateral part of the tibial, and near completion of skeletal growth. Intervention consists of epiphysiodesis of the lateral sides of the tibia and proximal fibula, and valgus opening wedge osteotomy of the proximal tibia and fibula.¹⁸ Unfortunately, in some individuals with adolescent Blount disease, there is shortening of the involved extremity that cannot be resolved by simple angular correction of the deformity.³²

De Pablos has advocated another technique. He treated a group of adolescent patients with asymptomatic bilateral tibia vara with asymmetric physeal distraction, demonstrating improvement in limb alignment and uniform closure of their physes.²⁰ The most appropriate indication for this technique is late-onset disease, or adolescent Blount disease with or without partial closure of the medial aspect of the proximal tibial growth plate (£50%) and no severe deformity of the proximal tibial epiphysis. Asymmetrical physeal distraction should not be used for infantile forms of Blount disease; it is indicated only in the adolescent who is near skeletal maturity.

External fixation has provided promising results in adolescent Blount disease (see Image below).^{29, 30, 31} Coogan et al prefer the use of a circular external fixation device and distraction osteogenesis instead of proximal tibial osteotomy and lateral hemiepiphysiodesis.²⁹

A: Anteroposterior radiograph of the knee in a 10-year-old boy demonstrating use of an external fixator (Taylor Spatial Frame; Smith & Nephew) in correction of tibia vara. B: 6-month postoperative anteroposterior radiograph of correction. Contributed by S. Standard, MD.



Advantages to their approach are the ability to perform angular correction in any plane, allowing procurvatum and internal tibial torsion to be addressed, in addition to proximal tibial varus; correction of distal tibial deformities with only slight frame modification; limb lengthening; and gradual correction of deformity with distraction osteogenesis, allowing for fine tuning of the alignment.³³ In addition, the stability of the frame allows for immediate weight bearing and a short hospital stay.

Their results demonstrate that distraction osteogenesis with an external fixator provides consistent correction of tibial deformities in these patients, with minimal morbidity. Correction was associated with significant improvement in symptoms and a high degree of patient satisfaction. They acknowledge disadvantages, which include the need for patient compliance in the operation of the device, potential pin fixation complications, and the possible need for a second anesthesia for device removal.

Postoperative details

In the postoperative period, carefully observe the neurovascular status for compromise, as this is a potential hazard. Compartment syndromes must be recognized and treated early. Fortunately, the gradual correction of dynamic external fixators make this less likely.

Related eMedicine topic:
Compartment Syndrome, Lower Extremity

Follow-up

In general, when osteotomy with internal fixation is performed, the osteotomy heals in 8 weeks. If enough callus is present to prevent change or loss of position, the cast is removed 5-6 weeks postoperatively. An above-the-knee cast is then applied with the knee in full extension and the foot and ankle free, allowing gradual partial to full weight bearing.¹⁸ Continuing follow-up care after initial surgical correction of the varus deformity is necessary because of the risk of recurrence. Infantile tibia vara has a good prognosis and recurrence of deformity is low when treated at a young age and early stage. However, older patients with advanced deformity (ie, stages IV-VI) are at increased risk of recurrence.²⁵

With the use of external fixators and distraction osteogenesis, gradual angular manipulation is begun 1 week after application of the external fixator and osteotomy. The correction takes place over the subsequent 2-3 weeks, depending on the severity of the deformity. After angular correction is achieved, the external frames are stabilized using additional threaded rods. The frames are generally removed 12 weeks postoperatively.²⁹

COMPLICATIONS

Section 8 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Complications associated with the treatment of Blount disease include loss of alignment, vascular impairment, pathologic fractures, wound infection, and malalignment.^{29, 34}

OUTCOME AND PROGNOSIS

Section 9 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

In long-term follow-up of infantile tibia vara, Doyle et al found that the outcome depends on the patient's age and severity of deformity at the time of intervention.²⁵ An understanding of the natural history of Blount disease is important for treatment. The prognosis in the infantile form of Blount disease must be considered separately from that in the adolescent form. Untreated infantile tibia vara is believed to be progressive. The literature has shown that partial or complete regression may occur in stages I-IV; however, stages V-VI do not show regression.²⁵

FUTURE AND CONTROVERSIES

Section 10 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Data on long-term follow-up of Blount disease are limited, and it is still unclear whether this limb abnormality predisposes patients to development of arthroses.^{1, 10, 25} With advances in treatment, retrospective studies on different treatment groups may show whether progression to arthrosis is a significant concern.

MULTIMEDIA

Section 11 of 12  

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Media file 1:  A 10-year-old boy with Blount disease. Marked obesity and bilateral genu varum is present. Courtesy of S. Standard, MD.
	View Full Size Image
Media type:  Photo

Media file 2:  Anteroposterior radiograph of the knee demonstrating the medial plateau depression and prominent metaphyseal beaking (Langenskiöld stage II-III) typical of infantile genu varum regardless of age of presentation.
	View Full Size Image
Media type:  X-RAY

Media file 3:  Anteroposterior radiograph representing important angles for staging typical for the adolescent form. Obvious varus deformity in the proximal tibia with no sloping or bar formation is present (bars do not occur in the adolescent form). A: Tibiofemoral angle. B: Metaphyseal-diaphyseal angle. C: Metaphyseal-epiphyseal angle.
	View Full Size Image
Media type:  X-RAY

Media file 4:  Diagram depicting the radiographic changes observed in the infantile form of Blount disease and their development with increasing age.
	View Full Size Image
Media type:  Graph

Media file 5:  A: Anteroposterior radiograph of the knee in a 10-year-old boy demonstrating use of an external fixator (Taylor Spatial Frame; Smith & Nephew) in correction of tibia vara. B: 6-month postoperative anteroposterior radiograph of correction. Contributed by S. Standard, MD.
	View Full Size Image
Media type:  X-RAY

REFERENCES

Section 12 of 12

• Authors and Editors
• Introduction
• Indications
• RELEVANT ANATOMY
• Contraindications
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

1. Hofmann A, Jones RE, Herring JA. Blount''s disease after skeletal maturity. J Bone Joint Surg Am. Sep 1982;64(7):1004-9. [Medline].
2. Andrade N, Johnston CE. Medial epiphysiolysis in severe infantile tibia vara. J Pediatr Orthop. Sep-Oct 2006;26(5):652-8. [Medline].
3. Wilson NA, Scherl SA, Cramer KE. Complications of high tibial osteotomy with external fixation in adolescent Blount's disease. Orthopedics. Oct 2007;30(10):848-52. [Medline].
4. Accadbled F, Laville JM, Harper L. One-step treatment for evolved Blount's disease: four cases and review of the literature. J Pediatr Orthop. Nov-Dec 2003;23(6):747-52. [Medline].
5. Blount WP. Tibia vara, osteochondrosis deformans tibiae. J Bone Joint Surg. 1937;19:1.
6. Bradway JK, Klassen RA, Peterson HA. Blount disease: a review of the English literature. J Pediatr Orthop. Jul-Aug 1987;7(4):472-80. [Medline].
7. Wenger DR, Mickelson M, Maynard JA. The evolution and histopathology of adolescent tibia vara. J Pediatr Orthop. Jan 1984;4(1):78-88. [Medline].
8. Davids JR, Blackhurst DW, Allen BL Jr. Radiographic evaluation of bowed legs in children. J Pediatr Orthop. Mar-Apr 2001;21(2):257-63. [Medline].
9. Henderson RC, Kemp GJ Jr, Greene WB. Adolescent tibia vara: alternatives for operative treatment. J Bone Joint Surg Am. Mar 1992;74(3):342-50. [Medline].
10. Schoenecker PL, Meade WC, Pierron RL, et al. Blount''s disease: a retrospective review and recommendations for treatment. J Pediatr Orthop. Mar-Apr 1985;5(2):181-6. [Medline].
11. Sevastikoglou JA, Eriksson I. Familial infantile osteochondrosis deformans tibiae. Idiopathic tibia vara. A case report. Acta Orthop Scand. 1967;38(1):81-7. [Medline].
12. Davids JR, Huskamp M, Bagley AM. A dynamic biomechanical analysis of the etiology of adolescent tibia vara. J Pediatr Orthop. Jul-Aug 1996;16(4):461-8. [Medline].
13. Golding JS, McNeil-Smith JD. Observations on the etiology of tibia vara. J Bone Joint Surg. 1963;45B:320.
14. Grover JP, Vanderby R, Leiferman EM, Wilsman NJ, Noonan KJ. Mechanical behavior of the lamb growth plate in response to asymmetrical loading: a model for Blount disease. J Pediatr Orthop. Jul-Aug 2007;27(5):485-92. [Medline].
15. Cook SD, Lavernia CJ, Burke SW, et al. A biomechanical analysis of the etiology of tibia vara. J Pediatr Orthop. Sep 1983;3(4):449-54. [Medline].
16. Arkin AA, Katz JF. The effects of pressure on epiphyseal growth: the mechanism of plasticity of growing bone. J Bone Joint Surgery Am. 1956;38:1056-76.
17. Langenskiöld A. Tibia vara. Osteochondrosis deformans tibiae. A survey of 23 cases. Acta Chir Scand. 1952;103:1.
18. Tachdjian MO, ed. The foot and leg: tibia vara. In: Pediatric Orthopedics. Vol 4. Philadelphia:. WB Saunders Co;1990:2835-50.
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Article Last Updated: Nov 18, 2008