Clinical Application of Growth Modulation Norman Ramrez MD

Clinical Application of Growth Modulation Norman Ramírez MD FAAOS/FAAP Pediatric Orthopedic Department Hospital De La Concepción San Germán – Puerto Rico

Hueter - Volkmann Mechanical compression slow longitudinal growth in the growth plate, sustained distraction produces increase growth, but the compression effect is greater. Mechanical effects on skeletal growth Stokes J Musculokel Neuron Interact 2002

GROWTH MODULATION The treatment of some childhood deformities such as angular deformities or length discrepancies is based on the concept of mechanically suppressing growth effect. Growth plate forces in the adolescent human knee: A radiographic and mechanical study of epiphyseal staples Bylski-Austrow JPO 2001

HISTORY In 1932, Phemister introduced concept of growth modulation through physeal arrest – Leg length discrepancy – Angular deformity Operative arrestment of longitudinal growth of bone in treatment of deformities Phemister JBJS 1933 In 1945, Haas demonstrated growth could be held back by a wire loop around physis – More importantly, proved that growth resumed when wire was removed Haas, S. JBJS. , 27: 25 -36, Jan. 1945

HISTORY In 1949, Blount set standard with epiphyseal stapling – Direct mechanical compression – Widely utilized and clinically proven Control of bone growth by epiphyseal stappling Blounts JBJS 1949

COMPLICATIONS • • • Breakage Migration Physeal closure Difficult removal Poor correction

The old center of growth modulation…. .

The newer center of growth modulation….

HISTORY In 2007 , Stevens proposed use of extraperiosteal nonlocking plate – Tension band construct – Long moment arm for correction • Hinges at edge of physis – Non rigid • Less concern of physeal arrest • Younger patients – One plate per physis

Why eight plates? Guided growth for angular correction Stevens JPO 2007

HISTORY In 1998, Metaizieau described using cannulated screws for distal femoral and proximal tibial Epiphysiodesis. He recommended fully threaded screws with at least 4 threads across the physis to create a physeal tether rather than a lag effect. Percutaneous Epiphysiodesis using transphyseal Srews Métaizeus JPO 1998

Complications Permanent Closure Of the Growth Plate

Growth Modulation Systems

Goyeneche JPO 2009 Less extrusion in small children ( 8 -plates) Correction was achieved in less time with staples Longitudinal growth inhibition is lower with 8 Plates Correction of bone angular deformities : Experimental analysis of staples versus 8 - plates Goyeneche JPO 2009

Wiemann JM JPO 2009 63 limbs staples: 39 limbs eight plates: 24 limbs same correction rate same complication rate Physeal stapling versus 8 -plates hemiepiphysiodesis for guide correction of angular deformity about the knee JPO 2009

Eric Gordon et al Posna 2011 Angular deformity: 188 pts Staples: 189 limbs Eight plates: 66 limbs Same correction rate ( 60 vs 68 %) Eight plates : less complication rates

Jelinek Int Orthop. 2012 Both Blount stapling and the 8 -plate technique are methods for correction of genu varum and valgum deformity in skeletally immature patients A shorter operating time for implantation and removal was noted for the 8 -plate technique The 8 -plate versus physeal stapling for temporary hemiepiphyseodesis correcting genu valgum and genu varum: a retrospective analysis of thirty five patients. Jelinek EM Int Orthop. 2012

Gottliebsen M Acta Orthop. 2013 Treatment time for the 2 treatment modalities was not significantly different in this randomized clinical trial. Tension-band plating and stapling appeared to have a similar effect regarding correction of genu valgum.

Park JPO 2016 Both techniques result in satisfactory correction of coronal angular deformity in patients with idiopathic genu valgum. The observed rate of correction was faster with PETS than TBP Hemiepiphysiodesis for Idiopathic Genu Valgum: Percutaneous Transphyseal Screw Versus Tension-band Plate Park JPO 2017

Treatment goals Normalize the mechanical axis Alleviate the symptoms Obviate the need for a corrective osteotomy Physeal stapling for idiopathic genu valgum Stevens JPO 1999

Indications Skeletally immature patients with significant and symptomatic angular deformity. Physeal stapling for idiopathic genu valgum Stevens JPO 1999

Indications Genun Valgum Genun Varus Angular deformities Leg Length Discrepancy Scoliosis

Radiological Parameters Lateral Distal Femoral Angle (LDFA) Medial Proximal Tibia Angle (MPTA) Mechanical Axis (MA) Comprehesive treatment of late –onset tibia vara Gordon JBJS 2005

Genum Valgum 10 -20° of valgus in a patient <10 years of age if line drawn from center of femoral head to center of ankle falls in lateral quadrant of tibial plateau in patient > 10 yrs of age Physeal stapling for idiopathic genu valgum Stevens JPO 1999

Genum Varus if line drawn from center of femoral head to center of ankle falls in medial quadrant of tibial plateau in patient > 10 yrs of age

Castañeda et al JPO 2008 48 pts Correction rate: Proximal tibia : 5. 5 degrees per year Distal Femur : 6. 7 degrees per year Hemiepiphysiodesis for correction of angular deformity about the knee Castañeda JPO 2008

Transphyseal Screws Results of screw epiphysiodesis for the treatment of limb lenght discrepancy and angular deformities Khoury JPO 2007

Leg Length Discrepancy

Concepts…. . Leg Length Discrepancy: 2 cm to 5 cm projected Distal Third Femur: 1 cm by year Proximal Third Tibia: 0. 6 cm by year No more of two years: Permanent Closure By Stages : 2 years / off / 2 years The role of guided growth as it relates to limb lengthening Peter M. Stevens J Child Orthop 2016

Scoliosis 35 22 Vertebral Body Stapling: a fusion less treatment option for growing child with moderate idiopathic scoliosis Betz Spine 2010 12 yrs old, Risser 0, premenarche 4 yrs P/O