ACL - Anterior Cruciate Ligament

Biodex Machine - A computer controlled, hydraulically operated flex/extension combo exercise machine that is in therapy offices. It is set up by a PT to safely provide resistance exercises for hamstring and quad development. It's primary purpose is to take performance parameters of the injured leg and compares it  to values obtained by also testing the good leg. (There may be other machines that do the same basic functions. A KinCom machine is another example.)


CPM - Continual Passive Motion Machine:  A small portable unit that cradles the injured leg and allows the patient to control the increase or decrease of leg flex by a wired remote control unit. This device can be useful to allow the patient an early start to flex exercises for many hours during the day. It's not a necessity since flexing can be done manually. However, the CPM would do flexing for many more hours than one would probably do it manually. especially considering the first week is a period of extreme tiredness form the sugery and/or pain medication.

I had a hospital version CPM which I started using a couple of hours after the reconstruction. The home CPM unit, I used for 8 hrs a day broken into 2 hr segments throughout the day. The unit had a maximum flex of 125 degrees which I achieved in 10 days. I returned the unit after 12 days and then manual home and therapy office flexing was implemented.

KT-1000/KT-2000 - This is a small hand held device that the OS assistant or the PT can use to determine relative looseness in the knee. The unit is strapped onto the leg in such a way that it can measure movement of the lower leg when the upper thigh is stationary. The test is performed when an individual is relaxing. Muscles are not utilized for the test. The device quantifies the looseness in the injured leg and then the test is performed on the good leg (if you have a good leg !). The results are then compared. An OS will sometimes recommend this test if some looseness is determined during his self evaluation. The test is not all that accurate but if it is repeated, perhaps during another visit, the test is then helpful in quantifying the looseness and determining if the ACL is providing functionality. Oftentimes, this test will be given when partial ACL tears are involved, a person has rehabbed to full muscle strength and an OS is determining if the individual has enough functionality in the ACL to recommend a return to sports. A custom sports brace may also be recommended due to ACL deficiencies.

MCL - Medial Cruciate Ligament

MRI - Magnetic Resonance Imaging:  An OS may send you to a facility to have an MRI of your knee. This does not hurt. It takes between 15-30 minutes in which they have you lay on a platform that the technician slides into a horizontal cylindrical unit. Your head is partially out of the MRI. They usually play music to keep you occupied, so it does not get too boring. As they take scans using the MRI, it sometimes sounds like a rat running on the outside of the cylinder - you usually here a gentle thumping sound. MRI scans are fairly accurate in identifying internal deficiencies such as cartilage tears and severed ACLs. A techniican or an OS may be able to identify a partial tear of an ACL but as far as I know, the MRI cannot assess the extent (percentage) of an ACL tear. Arthroscopy is usually the only way to really assess the extent of a partial ACL tear and all knee deficiencies. As a non-invasive tool, the MRI assists the OS in determining or confirming knee deficiencies.and helps prepare the OS for what is anticipated during arthroscopy.

Primus Machine - This is another therapy machine similar to the Biodex listed above.


OS - Orthopaedic Surgeon
PCL - Posterior Cruciate Ligament
PT - Physical Therapist or Physical Therapy