Epiphysiodesis is a surgical procedure in which the epiphyseal plate (growth plate or physis) of a long bone is intentionally destroyed, fused, or mechanically blocked to permanently or temporarily arrest bone growth at that site — distinct from epiphysiolysis, which refers to pathological separation of the epiphysis from the metaphysis, and from physeal fracture, which is traumatic disruption of the same structure. Unlike limb-lengthening procedures (e.g., distraction osteogenesis), epiphysiodesis shortens the longer limb or halts angular progression by selectively stopping growth on one side or at one site, relying on the patient’s remaining growth in the contralateral bone or on the opposite cortex to achieve equalization or realignment. The underlying mechanism exploits the biology of the physis: by obliterating the proliferative and hypertrophic cartilage cell columns responsible for longitudinal growth — through drilling, curettage, stapling, or tension-band plating — the surgeon converts the dynamic growth interface into static fibrous or bony tissue, permanently (open/ablative) or reversibly (tension-band/eight-plate). Epiphysiodesis is exclusively a pediatric and adolescent procedure; in skeletally mature patients, the physis has already fused and the procedure is anatomically irrelevant. The most commonly coded forms target the distal femur (27485), proximal tibia/fibula (27477), combined distal femur and proximal tibia/fibula (27479), distal tibia (27730), distal fibula (27732), or combined distal tibia and fibula (27734). It is commonly confused with hemiepiphysiodesis, which arrests growth on only one side of the physis to correct angular deformity (e.g., valgus or varus) rather than overall longitudinal discrepancy, though both use the same CPT code families.
“upon,” “on top of,” “over,” “at” — positional prefix indicating something situated above or on the surface of another structure
-physis
Greek φύσις (phýsis), from φύειν (phýein, “to grow”)
“growth,” “nature,” “that which has grown” — referring to the cartilaginous growth plate or bony outgrowth; the long-bone articular-end growth interface
Greek δέσις (désis), from δεῖν (deîn, “to bind, to tie”)
Noun-forming suffix — “binding,” “fusion,” “fixation” — surgical suffix denoting a procedure that creates fixation or fusion of a structure (cf. arthrodesis, tenodesis, spondylodesis)
The word entered English in the early 20th century as epiphysiodesis (noun), constructed directly from Greek components — from Greek ἐπιφύσις (epíphysis), meaning “an attachment, an outgrowth upon,” derived from epi- (“upon”) + phyein (“to grow”), combined with the surgical binding suffix -desis from deîn (“to bind”). The literal construction translates as “binding of that which grows upon” — a precise anatomic description of surgical fixation of the growth plate. The root physis (“growth”) connects Epiphysiodesis to the broader -physis ROOT FAMILY: apophysis (apo- + physis → “growth away from” → a non-articular bony prominence), diaphysis (dia- + physis → “growth through” → the bone shaft), and symphysis (sym- + physis → “growing together” → a cartilaginous midline joint). The suffix -desis is one of the most productive surgical suffixes in orthopedic terminology, appearing in arthrodesis, tenodesis, spondylodesis, and pleurodesis.
🔀 ALIASES / ALTERNATE TERMS
Epiphyseal(adjective form — used clinically in “epiphyseal arrest,” “epiphyseal stapling,” “epiphyseal fusion,” “epiphyseal bar”)
Growth plate arrest(lay/clinical synonym used in patient communication and operative consents; synonymous with epiphysiodesis in most clinical contexts)
Epiphyseal stapling(historical technique-specific synonym; refers to the original Blount stapling method — now largely replaced by tension-band plating but the term persists in older records and some current documentation)
Eight-plate epiphysiodesis / tension-band epiphysiodesis(technique-specific synonym for the reversible guided-growth variant using a figure-eight tension-band plate; used for both LLD and angular deformity; coded under same CPT families as open epiphysiodesis)
Hemiepiphysiodesis(variant procedure targeting only the medial or lateral half of the physis to correct angular deformity — valgus or varus — rather than overall limb length; often performed with eight-plate; coded identically to full epiphysiodesis — site and method drive CPT selection, not “hemi” prefix)
PETS (Percutaneousepiphysiodesis using Transphyseal Screws)(minimally invasive technique using cannulated screws percutaneously across the physis; less tissue disruption than open methods; still coded under the same site-specific CPT codes — method descriptor “any method” in CPT language captures this)
Percutaneous epiphysiodesis(minimally invasive drilling technique — Canale method or Phemister technique variant — performed through small stab incisions rather than open exposure; coded under site-specific CPT, same family)
Leg length discrepancy(the most common diagnosis driving epiphysiodesis — coded under M21.751, M21.752, M21.759, M21.761, M21.762, M21.769 depending on site and laterality)
Angular deformity(second major indication — valgus/varus — coded under M21.061, M21.062, M21.161, M21.162 or congenital equivalents depending on etiology)
🔗 RELATED TERMS
physis — the cartilaginous growth plate; the anatomic target of epiphysiodesis; composed of resting, proliferative, hypertrophic, and calcification zones — the hypertrophic zone is the most mechanically vulnerable and the site of most physeal fractures
Epiphysis — the rounded articular end of a long bone, separated from the metaphysis by the physis; gives the procedure its name; the epiphysis itself is not removed — only the intervening growth plate is targeted
metaphysis — the flared region of long bone between the physis and diaphysis; the zone into which the physeal cartilage ossifies; the drilling and curettage in ablative epiphysiodesis traverses from metaphysis through physis
Apophysis — shares the -physis root; a secondary ossification center at a musculotendinous attachment site — NOT a growth plate contributing to bone length; the site of apophysitis rather than epiphysiodesis
Epiphysiolysis — pathological slippage or separation of the epiphysis from the metaphysis through the physis; the most common form is SCFE (Slipped Capital Femoral Epiphysis, M93.001-M93.019); mechanistically the opposite of epiphysiodesis — one is pathological separation, the other is surgical fusion
Distraction osteogenesis — the alternative surgical strategy to correct LLD — instead of shortening the longer limb via epiphysiodesis, the shorter limb is lengthened by creating a controlled osteotomy and gradually distracting the bone ends; significantly more complex recovery
Leg length discrepancy — the primary indication for epiphysiodesis; acquired (post-traumatic, post-infectious, post-irradiation) or congenital; coded with site and laterality specificity under M21.7x or Q72.x for congenital forms
Hemiepiphysiodesis — growth arrest of only one side (medial or lateral) of the physis to produce guided angular correction; the eight-plate and tension-band plate techniques are most commonly used for this purpose; coded under same CPT family as full epiphysiodesis
Salter-Harris fracture — traumatic physeal injury classified by the Salter-Harris system (Types I-V); a common antecedent cause of growth disturbance and subsequent LLD that may ultimately require epiphysiodesis for correction
Bone age — critical concept for surgical planning; epiphysiodesis timing must be calculated based on skeletal maturity (bone age via Greulich-Pyle atlas or Risser staging) rather than chronological age — premature epiphysiodesis causes overcorrection; delayed epiphysiodesis is ineffective
Scanogram / Orthoroentgenogram — the standing full-limb AP radiograph used to measure true limb lengths before and after epiphysiodesis planning; CPT 77072 (bone age) and 73501/73521 (hip/knee standing films) are frequently co-billed in the workup
Radiologic examination, lower extremity — primary imaging for surgical planning and postoperative monitoring; long-leg standing films and bone age series are standard pre-procedure workup
CODING CORNER
🏥 ICD-10-CM CODES
Leg Length Discrepancy — Acquired (M21.7x — Primary Epiphysiodesis Indication; Site + Laterality Required)
Personal history of other musculoskeletal disorders (use for history of prior physeal injury driving LLD)
Z47.89
Encounter for other orthopedic aftercare (post-epiphysiodesis follow-up encounter — commonly used for plate removal encounter)
🔧 COMMON CPT CODES (Epiphysiodesis — Surgical Arrest of Epiphyseal Growth)
CPT Code
Description
27477
Arrest, epiphyseal (epiphysiodesis), any method; distal femur
27479
Arrest, epiphyseal (epiphysiodesis), any method; combined distal femur, proximal tibia and fibula
27485
Arrest, epiphyseal (epiphysiodesis), any method; distal femur — NOTE: distinct from 27477 by approach/technique per AMA guidance; confirm payer-specific bundling rules
Arrest, epiphyseal (epiphysiodesis), open; distal tibia and fibula
27740
Arrest, epiphyseal (epiphysiodesis), any method; combined, proximal and distal tibia and fibula
27742
Arrest, epiphyseal (epiphysiodesis), any method, combined, proximal and distal tibia and fibula; and distal femur
20150
Excision of epiphyseal bar, with or without autogenous bone graft (used when epiphyseal bar/bony bridge is resected prior to or instead of formal epiphysiodesis)
73521
Radiologic examination, hips, bilateral, with pelvis (pre-op planning scanogram — long cassette)
77072
Bone age studies (pre-op skeletal maturity assessment — frequently billed during epiphysiodesis workup)
73560
Radiologic examination, knee; 1 or 2 views (post-op monitoring)
73562
Radiologic examination, knee; 3 views
73564
Radiologic examination, knee; complete, 4 or more views
27334
Arthrotomy, with synovectomy, knee; anterior or posterior (adjacent — sometimes performed simultaneously if joint pathology identified intraoperatively)
⚠️ Coding Note: The CPT descriptor “any method” in codes 27477, 27479, 27740, and 27742 is critical — it captures open/ablative (Phemister technique), percutaneous drilling (Canale technique), tension-band/eight-plate (guided growth), and PETS screw methods under the same code; do not attempt to up-code or add-on a separate CPT for technique variation. On inpatient profee claims, the diagnosis driving epiphysiodesis must be coded to the highest level of specificity — laterality and site are required for all M21.7x codes, and failure to specify femur vs. tibia vs. fibula as the affected segment will result in an unspecified code that may trigger a medical necessity edit or payer denial, particularly under UHC and BCBS commercial plans which require site-specificity for surgical authorization. An undercoding alert for inpatient pediatric orthopedic encounters: when documentation states “limb length inequality,”“short leg,” or “unequal leg lengths” without specifying which bone is the source of discrepancy, query the surgeon for the specific bone(s) involved before defaulting to unspecified codes — the operative report’s anatomic target (e.g., “distal femoral physis”) is your best secondary source. For plate/staple removal following a prior epiphysiodesis encounter, report 27334 or hardware removal codes as appropriate with Z47.89 as a supporting diagnosis. Modifier -54 (Surgical Care Only) and -55 (Postoperative Management Only) apply when the operating surgeon and follow-up provider are different — common in pediatric referral centers where the index surgery occurs at a tertiary center but post-op management transfers to a local orthopedist.
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