Tibial Tubercle

Transtibial (Below-Knee) Amputation Prostheses. By definition, the residual limb of a functional transtibial amputee includes tibial tubercle into which the quadriceps tendon inserts so as to retain knee extension capability. The prosthesis for a transtibial amputee, in general, consists of a socket with an optional insert, adapter hardware to attach the socket to the shank, and an artificial foot. In addition, the prosthesis often includes some means of auxiliary suspension. 

To minimize the graft harvest site morbidity, the defect in the tibial tubercle due to bone plug harvesting should be filled with cancellous bone obtained at the time of creating the tibial tunnel. 

The tibial tubercle begins to ossify between 7 and 9 years of age, beginning distally, and progressively enlarging proximally and anteriorly while the main tibial ossification centre expands downward towards the tubercle. A section of epiphyseal cartilage usually remains between these two ossification centers until close to physeal maturity (Ogden 1984). The ossification centre for the tibial tubercle... 

Fig. 14.9. Classification of tibial tuberosity avulsion injuries 1A,1B, separation of the distal portion of the physis 2A,2By the separation involves the ossification centres of the tibial tubercles and tibial epiphysis 3A,3B, fracture/separation of the entire tubercle. In addition, there may be fracturing through the avulsed fragment (type B)...

The exact aetiology of Osgood-Schlatter disease is controversial. The generally excepted idea is that of a traction apophysitis of the patellar ligament on the tibial tubercle. It was described independently in 1903 by Osgood in the English literature and Schlatter in the German literature. This condition is the commonest cause of knee pain in preadolescents. 

The lesion occurs when the tibial tubercle is in the apophyseal stage and the secondary ossification centre has appeared. The tibial tubercle apophysis appears between 7-9 years of age, and repeated traction injuries cause microfractures in the apophysis (Lazerte 1958). 

The onset is usually gradual, with patients complaining of pain over the tibial tubercle or patellar region after activities sucb as running or jumping. An acute onset of pain with no preceding symptoms should alert the clinician to the possibility of a tibial tubercle avulsion. 

Ultrasound will show the soft tissue swelling and thickening of the overlying soft issue and tendon. MR imaging will show fragmentation of the tibial tubercle, heterotopic ossification within the distal patellar tendon and non-specific oedema with a reactive bursitis. 

Four fmgerbreadths distal to the tibial tubercle (TT) and two finger-breadths lateral to the tibial crest, the electrode is inserted through the tibialis anterior about one inch. 

Through the quadriceps tendon onto the tibial tubercle. 

Plain radiographs provide many indications suggestive of acute ACL rupture avulsion fracture of the lateral tibial plateau, or Segond fracture, which is in fact an injury to the lateral joint capsule, avulsion of the Gerdy s tubercle and a lateral notch lesion, which is a compression fracture of the lateral femoral condyle of more than 2 mm seen on lateral radiograph. A tibial rim lesion on the posterolateral lip of the lateral tibial plateau can also be found alone or associated with the lateral notch lesion and is termed a kissing contusion. Joint effusions can also be detected on simple radiographs (Fig. 20.6). 

Macroscopic observation of ACL tibial footprint, (a) ACL and lalraal meniscus arc overlapped anteriOTly, and the lateral meniscus slips under the substratum of the ACL posteriOTly. (b) After resection of ACL and lateral moiiscus attachmenL AH anterior hom of lateral mcmiscus, MM medial meniscus, UT lateral intercondylar tubercle, M7T medial intercondylar tubtucle, white dot area ACL tibial footprint, blue dot area attachment of anterior hom of lateral meniscus... 

Fig. 4.6 Ideal tunnel position for (a) single-bundle reconstruction, (b) double-btmdle reconstruction from our results. White dot line, L-shaped ridge red line, attachment of anterior horn of lateral meniscus blue dot line, anterior margin of the medial and lateral intercondylar tubercle yellow circle, tibial tunnel for single-bundle ACL reconstruction red circle, tibial tunnel of anteromedial bundle for double-bundle ACL reconstruction blue circle, tibial tunnel of posterolateral bundle for double-bundle ACL reconstruction...

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