**3.2 Allografts**

200 Modern Arthroscopy

On lateral X rays it is possible to locate the various centers of the tibial ACL foot print. Using the Stäubli and Rauschning technique (Fig. 4), the footprint center is located at 43 % of the antero-posterior diameter of the tibia (Stäubli & Rauschning, 1994) while the center of the

Contrary to a common belief, the bone-patellar-tendon-bone (BPTB) remains the most frequently used autograft (Shelton and Fagan, 2011), but hamstring and quadriceps tendon

> **Knee Tightness**

Slightly lower

**Residual Weakness** 

Quadriceps muscle

Ham-

Quadriceps mucle

**Extension deficit** 

strings Low High

**Patient Satisfaction** 

High High

Low High

AMB is located at 36% and the center of the PLB at 52% (Colombet et al., 2006).

**Failure rate** 

Higher

Table 1. This table summarizes the factors to be considered in ACL autograft selection (from

**3.1.1** BPTB autograft, which has two bone plugs at each of its extremities, affords the most secure fixation, a low failure rate and high rate of patient satisfaction. This is the graft of choice among team physicians dealing with high level professional athletes (Pandarinath et al., 2011). However, it is associated with increased anterior knee pain and numbness with a greater incidence of extension loss and long term osteoarthritis of the knee. Residual anterior knee pain can be decreased by filling the bony defects of the harvesting sites, and numbness can be prevented by saving the infrapatellar branch of the saphenous nerve

**3.1.2** Hamstring grafts are associated with less harvesting morbidity than BPTB, however, they exhibit a slighter degree of laxity, especially in females. Their harvesting weakens flexion strength of the knee and may account in the reported incidence of graft failure. They are usually fashioned in a quadrupled stranded graft using both gracilis and semitendinosus

**3.1.3** Quadriceps tendon has a low incidence of anterior knee pain and almost no residual numbness. It can be fashioned with or without bone plug. After harvesting, quadriceps deficit is temporary. Clinical outcome is excellent with residual laxity similar to BTB both in males and females, without extension deficit. For many, this is the graft of choice for ACL

**3. Graft selection** 

grafts are common alternative.

**Anterior knee pain** 

**Anterior knee Numbness** 

BPTB High High Low High

ceps Low Low Low High

All three graft types exhibit strength values above 2,000 N.

revision or posterior cruciate ligament reconstruction.

string Low Low Slightly

**3.1 Autografts** 

**Graft type** 

Ham-

Quadri-

Shelton and Fagan, 2011).

during harvesting.

tendons.

Allografts avoid harvesting tendons with their drawbacks, i.e anterior knee pain or numbness. In countries where legal issues are important, especially the United States (USA), allografts became the graft of choice for ACL reconstruction.

**3.2.1** Currently, three kinds of allografts are available: chemically treated, irradiated and/or fresh frozen. Due to their poor mechanical properties, chemically treated or irradiated allografts are gradually abandoned (Krych et al., 2008). Currently, fresh frozen allografts are the most widely used. Tissue banks insure the proper donor selection as well as bacterial and viral screening. With the current infection control protocols, the incidence of viral or bacterial contamination is null. Graft quality is an issue and donor age must be known. Thus the choice of the tissue bank is critical.

**3.2.2** Fresh frozen tibialis anterior or posterior tendons, Achilles' tendon with bone plug and BPTB are the most widely used. The outcome is similar to autografts (Foster et al., 2010) however, allografts have significantly lower normal stability rates than autografts (Bach et al.,2005; Prodromos et al., 2007).

Most of the US authors do not recommend the use of allografts in young and high demanding athletes. Also the use of allografts add a significant cost to the procedure (c.a. \$ 3,000 in the USA). Thus, for the authors, the use of allografts which lead to inferior results compared to autografts at an increased cost remains questionable
