The native anterior cruciate ligament (ACL) in the knee joint provides a critica
ID: 3474712 • Letter: T
Question
The native anterior cruciate ligament (ACL) in the knee joint provides a critical role in stabilising the joint during dynamic activities. You have been asked by an Orthopaedic surgeon to evaluate the biomechanical characteristics of a new artificial anterior cruciate ligament (nACL), which has been developed as part of an international team of surgeons, and sponsored by an international medical device company. The objective of the design was to create an artificial structure that closely represents the native material properties of the human ACL. The surgeon believes that this new artificial ACL will represent a breakthrough in the repair of ACL tears, leading to superior clinical outcomes compared to using either bone-patellar tendon-bone (BPTB) graft, or hamstring tendon (HT) graft reconstructions.
Prepare a proposal for how you would evaluate the in-vitro biomechanical properties of the nACL. Use the following headings to develop your proposal:
1. Study design (i.e. what groups will you be comparing? Human or animal tissue? Selection criteria? Sample size? Justify your decisions.)
2. Measurement of viscoelastic non-destructive and destructive material properties (which ones and why?).
3. Measurement parameters from item 2 above, and how you would calculate them.
4. In-vitro testing considerations, including advantages and disadvantages, and how limitations could be overcome.
Explanation / Answer
1) The in-vitro biomechanical properties of new anterior cruciate ligament (nACL) can be evaluated by comparing it's efficiency with other treatment groups. A rrandomised clinical trial consisting of three groups can be conducted. One group treated with nACL, second group treated with bone petallar tendon bone graft and the third group treated with hamstring tendon graft.
The selection criteria will be all those individuals between 20-60 years of age requiring repair of anterior cruciate ligament. Persons with diabetes, hypertension and other ststemic diseases requiring long term treatment are excluded. The sample size in each of the three groups should be at least 30 for the results to be reliable and valid.