ACL Surgery - Hamstring Tendon versus Patella Tendon Grafts

Effects of Removing Part of the Tendon

1 Introduction
2 Hamstring vs Patella Tedon Graft Rehabilitation >
3 Effects of Removing Part of the Tendon
4 Suitability of Hamstring and Patella Grafts >
5 Surgery vs Conservative Treatment >

How can the patient function normally if either part of their Patella tendon or one of their Hamstring tendons is removed for use as an ACL graft?

"The answer to this question has to be based on perspective. In the short term (12-18 months following surgery), either graft site is likely not to be functioning normally. Lots of research shows these tissues are still weak at this stage. But all biological tissues have the ability to repair and re-grow if the stimulus is right. Players with these types of injury and surgical repair need to be rehabilitated over long periods not merely until they have returned to play, in order to maximise the potential functional return of the graft sites.

"Key to returning to normal function is the rehabilitation, rather than the surgery. The majority of studies indicate that regardless of type of surgery, outcome is good if the patient is compliant and follows a well structured rehabilitation regime over a prolonged period."

Don't they get patellofemoral or hamstring problems?

"It is very rare to get Hamstring problems. In the review of literature we conducted it was rarely, if ever, a reported complication. Contrary to a popularly held belief, both types of operations get Patellofemoral joint pain (PFP). This is more a result of poor management of the things which cause PFP rather than of the type of surgery.

"PFP is caused by alteration in the stresses to which the patella and surrounding structures are exposed. There are two main causes of alteration of joint stresses. One cause is changes in the 'dynamic Q angle' (see note below), which is related to increased femoral medial rotation (turned in thighs), knee valgus (knock knees) and/or tibial lateral rotation (rolled out shins). These can of course be controlled if the patient is appropriately trained.

"The other main cause of PFP is weakness of the Quadriceps muscles. This means that the Patella is no longer pulled as deeply through the trochlear groove (of the thigh) during knee extension activities, so there is less joint surface contact and stresses per unit area are increased, leading to altered loading and pain. Failure to ameliorate Quadriceps inhibition (improve the weakness due to swelling or pain), will obviously facilitate the onset of this."

Note: The Q-Angle refers to the 'quadriceps angle', which is a measurement of patellofemoral joint mechanics. The Q Angle is measured at the intersection of two lines: one drawn from a bony point at the front of the hip to the mid-point of the knee cap and the other from the mid-point of the knee cap to the insertion point for the Patella tendon, at the upper part of the shin. Research has shown that this Q Angle can be areasonable estimate of the muscle force vectors (direction of muscle pull) over the patellofemoral joint. Further research has suggested that there is an increase risk of PFP if the Q Angle greatly exceeds 15 degrees.

< top of page

4 Suitability of Hamstring and Patella Grafts >

Mueller Pro Style Hinged Knee Brace (deluxe)

Our Price
£69.99

The patented Tri-Axial adjustable hinges provide excellent protection for skiing and sports. Ideal for prevention and...

Effects of Removing Part of the Tendon

Recommended Products for ACL Knee Injury & Reconstruction

ACL Knee Braces & Supports

Ice Packs & Compression

ACL Rehabilitation Kit