- See:
-
Growth of Proximal Tibial Epiphysis:
-
Avulsion of the Tibial Tubercle:
- Discussion:
- injuries of prox tibial epiphysis are rare (3 % of lower extremity epiphyseal frx);
- injury is uncommon because knee ligaments bypass proximal tibial epiphysis and instead insert more distally;
- proximal tibial epiphysis is becomes separated from metaphysis, however,
nutrient vessels are usually not damaged &
therefore future growth is not disturbed;
-
frequency of Salter Harris Injuries:
- SH type I: 15 %;
- SH type II: > 40 %;
- most common proximal tibial epiphyseal frx ( > 40%);
- injury occurs primarily in older children and adolescents;
- SH type III > 20 %;
- SH type IV > 15%
- SH type-V: 2 %
- Anatomy:
- attachment of tibial collateral ligament to metaphysis transmits stress to metaphysis rather than to epiphysis;
- w/ growth, proximal tibial physis fuses asymmetrically from posterior to anterior;
- Mechanism:
-
hyperextension force that displaces tibial metaphysis posteriorly;
-
flexion force may also cause a Salter-Harris type-II or III injury;
- w/ growth, proximal tibial physis fuses asymmetrically from posterior to anterior, &
flexion force may cause fracture anteriorly where the physis is still open;
- Physical Findings:
- severe pain & swelling & limitation of extension & flexion of knee;
- beware of
compartment syndrome;
- tenderness usually is present over proximal tibial physis distal to joint line, but soft-tissue swelling may make it difficult to localize tenderness.
- posterior displacement of proximal tibial metaphysis will produce visible & palpable concavity anteriorly at level of tibial tuberosity;
- Radiographs:
- non-displaced frx may not be visible on plain AP or lateral x-rays so consider oblique radiographs;
- frx lines may extend upward thru epiphysis or distally into metaphysis.
- small fleck of bone at periphery of metaphysis may be only finding;
- occasionally, CT scanning or MRI may be helpful.
-
stress x-rays in coronal & sagittal planes may be helpful;
- if pt has sustained abduction injury, medial portion of physis will open w/ valgus stress;
- on lateral radiograph, posterior portion of physis may open w/ hyperextension stress.
- Non Operative Treatment
- most SH I & II frx can be treated w/ closed reduction & immobilization.
- Operative Treatment:
- Displaced Salter-Harris type-III and IV Frx;
- closed reduction & percutaneous pinning;
- two smooth K wires or small cannulated screws are inserted horizontally across epiphysis w/o crossing the physis;
-
open reduction:
- indicated if anatomic reduction cannot be obtained;
- pes anserinus may be interposed in frx which may prevent reduction;
- Post Reduction Care:
- always beware of
compartment syndrome;
- limb is immobilized in above-knee splint w/ knee in 10-20 deg of flexion;
- after several days, above-knee
cast is applied & is worn until frx unites;
- fracture union usually occurs in six to eight weeks;
- Complications:
-
angular deformity:
- most common complication (upto 30%);
- most common after SH type-IV frx;
-
limb-Length Deformity:
- limb-length discrepancy occurred in 19 % (11) of 57 pts in two series, & both type-I & type-II fractures can cause growth arrest;
-
neurovascular injuries:
- commonly occur because popliteal artery lies adjacent to tibial epiphysis & is tethered as anterior tibial artery crosses
interosseous membrane & courses into
anterior compartment;
- sagittal plane displacement can injure either the
popliteal or
anterior tibial artery.
- see popliteal artery injury follow knee dislocation;
- because of high risk of vascular injury w/ this frx,
arteriogram is indicated if foot is cool & pale or if any abnormality in pulses is noted.
- vascular impairment may be subtle;
Trauma involving the proximal tibial epiphysis.
Epiphyseal fractures of the proximal tibia.
Fractures of theTibia through the Proximal Tibial Epiphyseal Cartilage. Shelton, W.R. and Canale, S.T.
JBJS 61-A, 1979. 167-173.
Fractures of the Proximal Tibial Epiphyseal Cartilage. Aitken, A.P. CORR, 1965; 41: 92-97
Fractures of the Proximal Tibial Epiphysis Burkhart, S.S. and Peterson, H.A. JBJS. 61-A, 1979. 996-1002.
