blounts disease.pptx

Blounts Disease

1. BLOUNTS DISEASE DR AKHIL JOSE

2. HISTORICAL BACKGROUND ERLACHER (1922) –first description of tibia vara and internal rotation Walter BLOUNT(1937)-described tibia vara

3. Blount: An osteochondrosis similar to coxa plana and madelung deformity but located at the medial side of proximal tibial epiphysis

4. Anders Langenskloid (1952) - radiographic changes and stages of disease in scandinavian population

5. synonyms Infantile tibia vara Erlachers disease Blount-barber disease Subepiphyseal osteochondropathy Non rachitic bow legs Osteitis deformans tibia

6. Secondary effects -internal torsion of tibia -insufficient ossification of the medial portion of medial tibial condyle Streched LCL

7. ANATOMY Genu varum is a normal physiologic process in children genu varum (bowed legs) is normal in children less than 2 years   genu varum migrates to a neutral at ~ 14 months continues on to a peak genu valgum (knocked knees) at ~ 3 years of age  genu valgum then migrates back to normal physiologic valgus(<15) at ~ 7 years of age

8. Types 2 types 1- Infantile -begins before 8 years of age 2- Adolescent - begins after 10 years of age but before skeletal maturity A) b/w 10 and 13 years -partial closure of epiphysis - trauma/infection B) b/w 10 and 13 years –black and obese children-no distinct cause

9. INFANTILE BLOUNTS DISEASE progressive pathologic genu varum centered at the tibia in children 2 to 5 years of age. Diagnosis- presence of a genu varum /flexion/internal rotation deformity and confirmed radiographically with an increased  metaphyseal-diaphyseal angle. Treatment - bracing to surgery (patient age, severity of deformity, and presence of a physeal bar .)  

10. ETIOLOGY Idiopathic more common male > female bilateral in 50 % Altered enchondral ossification Risk factors overweight children early walkers (< 1 year) Hispanic and African American

11. Pathophysiology multifactorial -but related to mechanical overload in genetically susceptible individuals excessive medial pressure produces an osteochondrosis of the medial proximal tibial physis and epiphysis ( osteochondrosis can progress to a physeal bar)

12. Intra articular pathology Enlargement and hypermobility of medial meniscus Depression of anterior aspect of medial femoral condyle Depression of posteromedial plateau of tibia

13. type I to IV consist of increasing medial metaphyseal beaking and sloping type V and VI have an epiphyseal- metaphyseal bony bridge (congenital bar across physis ) At stage 6 – medial portion of epiphysis fuses at 90 degree downward angle

14. PRESENTATION Physical examination genu varum /flexion/internal rotation deformity usually b/l in infants lateral thrust on walking Waddling gait may exhibit positive 'cover-up test'  often associated with internal tibial torsion leg length discrepancy

15. usually NO tenderness, restriction of motion, effusion Bony hard non tender prominence –palpable at the medial epiphysiometaaphyseal junction SIFFERT KATZ sign-as the extended knee is slightly flexed---medial femoral condyle engages tibial medial plateau depression and sublaxates posteromedially ( varus instability at 15 degree knee flexion)

16. Long standing neglected cases’ -slight flexion deformity added Unstable joint-lax ligaments Medial compartment OA knee

17. IMAGING Radiographs standing long-cassette AP radiograph of both lower extremities ensure that patella are facing forwards for evaluation (commonly associated with internal tibial torsion) findings suggestive of Blounts disease medial and posterior sloping of proximal tibial epiphysis(short , thin,wedged,irregular ) varus focused at proximal tibia severe deformity(asymmetric bowing) sharp angular deformity(progressive )

18. metaphyseal breaking   different than physiologic bowing which shows a symmetric flaring of the tibia and femur Often palpable Not diagnostic Pathognomic -progressive disease

19. DRENNAN ANGLE

20. Other investigations Ct scan to r/o physeal bar Double contrast arthrography and arthroscopy –intra articular pathology(articular surface defects,medial meniscus) Histological findings’ -delayed ossification of medial epiphysis and proximal tibia -cell hypertrophy Dense cellularity Fibrocartilage islands Abnormally large group of capilaries

21. DIFFERENTIAL DIAGNOSIS Persistent physiological varus R ickets   osteogenesis imperfecta Multiple Episphyseal Dysplasia( fairbanks d/s)   Spondyloepiphyseal dysplasia   metaphyseal dysostosis (Schmidt, Jansen) focal fibrocartilaginous defect thrombocytopenia absent radius proximal tibia physeal injury (radiation, infection, trauma)

22. RICKETS MULTIPLE EPIPHYSEAL DYSPLASIA SPONDYLO- - EPIPHYSEAL DYSPLASIA

23. TREATMENT Nonoperative BRACE TREATMENT WITH KneeAnkleFootOrthosis   indications Stage I and II in children < 3 years   technique bracing - approximately 2 years for resolution of bony changes outcomes improved outcomes if unilateral poor results - obesity  and  bilaterality if successful, improvement - within 1 year

24. KAFO Prefered by Railey Valgus force at 3 points 23 hrs /day Full weight bearinng

25. ELASTIC BLOUNT BRACE 1987 Wide elastic band just distal to knee joint

26. OPERATIVE PROXIMAL TIBIA/FIBULA VALGUS OSTEOTOMY    overcome the varus /flexion/internal rotation deformity indications Stage I and II in children > 3 years   Stage III, IV, V, VI age ≥ 4y (all stages)   failure of brace treatment   progressive deformity metaphyseal-diaphyseal angles > 20 degrees outcomes risk of recurrence is significantly lessened if performed before 4 years of age

27. OSTEOTOMY GOALS OF CORRECTION overcorrect into 10-15° of valgus because medial physeal growth abnormalities persist   distal segment is fixed in valgus, external rotation and lateral translation

28. RAB OSTEOTOMY( metaphyseal /oblique) A-transverse incision at tibial tubercle B-y shaped periosteal incision C-insertion of steinman pin D-mark saw and osteotomy(prevent overpenetration ) E-oblique cut beneath pin F-rotation of osteotomy and fixation with lag screw

29. CHEVRON OSTEOTOMY

30. may

31. PHYSEAL BAR RESECTION indication at least 4y of growth remaining technique perform together with osteotomy interpositional material is usually fat or PMMA

32. COMPLICATIONS 1.Compartment syndrome (with high tibial /fibular osteotomy)-prophylactic release of anterior compartment 2.CPN palsy 3.anterior tibia artery injury 4.Recurrence of tibial vara severe cases-- physeal bar-- progressive varus after a well executed proximal tibial valgus osteotomy--- require a lateral tibial hemiepiphysiodesis or physeal bar resection

33. Physeal bar MC cause of recurrence Greene criteria(CT scan) 1.age>5 2.medial physeal slope 50-70 degree 3.langenskiold grade 4 or more’ 4.body weight >95 th percentile 5.black girls who meet previous criteria

34. PROGNOSIS Best outcomes  early diagnosis and unloading of the medial joint with either bracing or an osteotomy Young children with stage II and stage IV can have spontaneous correction

35. Infantile versus Adolescent Blount's Infantile Blounts Adolescent Blounts Age 2-5yrs >10yrs Bilaterally 50% bilateral Usually unilateral Risks Early walking, large stature, obesity Obesity Classification Langenskiold No radiographic classification Severity More severe physeal/ epiphyseal disturbance Less severe physeal/ epiphyseal disturbance Bone Involvement Proximal medial tibia physis , producing genu varus , flexion, internal rotation, AND may have compensatory distal femoral VALGUS Proximal tibia physis , AND may have distal femoral VARUS and distal tibia valgus Natural History Self-limited - stage II and IV can exhibit spontaneous resolution Progressive, never resolves spontaneously (thus bracing unlikely to work) Treatment options Bracing and surgery Surgery only

36. Adolescent Blount's Disease progressive, pathologic genu varum centered at the tibia in children > 10 years of age.  Treatment is generally surgical epiphysiodesis or osteotomy depending on severity of deformity and amount of growth left. 

37. ETIOLOGY Less common less severe more likely to be unilateral more likely to have femoral deformity obesity African-American descent Pathophysiology- dyschondrosis of medial physis  of proximal tibia – multifactorial-  mechanical overload in genetically susceptible individuals

38. PRESENTATION hallmark is genu varum deformity obesity usually unilateral (compared to bilateral in infantile Blount's) limb-length discrepancy secondary to deformity mild to moderate laxity of medial collateral ligament May have femoral varus and distal tibia valgus

39. RADIOGRAPHIC findings s/o adolescent Blount's disease narrowing of the tibial epiphysis  widening of the medial tibial growth plate occasional widening of the lateral distal femoral physis metaphyseal breaking less commonly seen with adolescent Blount's

40. Treatment Surgical 1. Lateral tibia and fibular epiphysiodesis 2. Proximal tibia/fibula osteotomy 3. distal femoral osteotomy or epiphysiodesis

41. Lateral tibia and fibular epiphysiodesis indications mild to moderate deformity with growth remaining outcomes up to 25% may require formal osteotomy due to residual deformity transient hemiepiphysiodesis tether physis with 8-plates or staple may remove implant once correction is achieved simple allows for gradual correction is children with adequate growth remaining b. permanent hemiepiphysiodesis obliteration of physis through small, lateral incision limited surgery overcorrection is uncommon cannot correct rotational deformity up to 25% may require formal corrective osteotomy

42. Proximal tibia/fibula osteotomy indications more severe cases in the skeletally mature - valgus producing tibial osteotomy and plating   - external fixation goals of correction overcorrection to valgus not indicated (as is the case in infantile Blount's) strive for neutral mechanical axi

43. High Tibial Osteotomy With Rigid Internal Fixation   variety of techniques, including closing wedge, opening wedge, dome, serrated and inclined osteotomies variety of fixation devices including cast, pins and wires, screws, plates and screws post-op limited weight bearing with use of crutches for 6-8 weeks immediate correction potential for neurologic injury due to acute lengthening potential for compartment syndrome

44. Osteotomy With External Fixation And Gradual Correction perform osteotomy, and connect frame that allows for gradual correction Taylor Spatial Frame or Ilizarov ring external fixator  post-op usually 12-18 weeks of treatment are needed gradual correction limits neurovascular compromise and risk for compartment syndrome allows for correction of deformity in all planes pin site infection duration of treatment bulk of construct

45. Distal Femoral Osteotomy Or Epiphysiodesis indications for distal femoral varus deformity of 8 degrees or greater

46. REFERENCES Campbell’s Operative Orthopaedics 14th edition (2021 ) Apley's System of Orthopaedics and Fractures TUREK orthopedic principles and application https://pubmed.ncbi.nlm.nih.gov/ https://www.orthobullets.com/