As I have discussed in this course, patients with posterolateral corner injuries that require surgery come in two different categories.

One is the acute (just happened) knee injury in which the operation is done fairly soon (within a week or two) – these are usually dislocated knees where damage also exists to other ligaments and soft tissues. The other category is the chronic knee where the injury occurred a long time ago and was not treated effectively.

In my experience, patients with chronic knee problems can be more difficult to treat because usually, there is some arthritis in the joint and they have typically undergone previous operations that failed to solve pain and instability. Therefore, when we talk about outcomes, or the results of surgery, it is important to understand that there are differences in what we can expect to accomplish between these two categories.


What is a good outcome?

The first goal of posterolateral surgery is to restore stability to the knee joint so that it does not collapse (or feel like it may give-way) during activities. As you have seen from the Rehabilitation section of this course, it takes many months of exercises and work with a physical therapist to regain normal knee motion, muscle strength, and function. Usually, if the postoperative course goes well with no complications or reinjuries, the patient will also experience a significant reduction in pain that was such a problem before surgery.

In terms of what patients can expect when the rehabilitation program is finished, this is based on the presence of pre-existing arthritis, if a significant amount of meniscus tissue was removed, and if the graft(s) heal and mature fully. Some patients are able to return to the same level of activity that they enjoyed before their knee injury. However, in my experience, most have to accept a decrease in their sports activities so that they do not make the arthritis worse with heavy impact-loading. I have found that most patients who have chronic, long-standing posterolateral problems are so grateful after surgery that they can finally walk normally without pain that they accept the limitations I recommend in terms of strenuous sports. Most are able to perform low-impact activities such as swimming, bicycling, and light recreational activities such as doubles tennis.

At my Center, we have conducted a series of clinical studies on 94 patients to determine the outcome of the different posterolateral operations I discussed in Part 5. All of the patients followed our rehabilitation program described in this course. Below is a summary of our findings.


Anatomic Posterolateral Reconstruction

We followed a consecutive group of patients that had an anatomic FCL bone-patellar tendon-bone (B-PT-B) reconstruction 2 to 13.7 years postoperatively (reference #2). The ACL and/or PCL were also torn in these patients and these damaged cruciate ligaments were also reconstructed during the posterolateral procedure.

We found that 93% of the patients had knee stability restored (normal lateral joint opening and external tibial rotation). All patients had at least 0° to 135° of knee motion.

Significant improvements were found in our rating scales for pain, swelling, the patient rating of the overall knee condition, walking, and stair climbing.

At follow-up, all but one of the patients were participating in mostly low-impact athletics (swimming, bicycling) without symptoms and 1 patient was participating in sports that involved pivoting and cutting with pain and limitations against advice.


Femoral-Fibular Posterolateral Reconstruction

We have completed two clinical investigations on the femoral-fibular posterolateral reconstruction for chronic knee instability (references #1,3). Here, I will discuss the recently completed long-term follow-up of this operation in a group of 27 patients who were evaluated a mean of 15 years (range, 4 to 19 years) after surgery.

This was a complicated group of patients that presented to us for treatment, as 37% had undergone a prior posterolateral procedure that had failed, 81% had a prior failed or untreated cruciate ligament rupture, 70% had knee arthritis, and 78% had problems with daily activities.

We found that 63% of the patients had knee stability restored. Still, there were significant improvements in the scores for pain, swelling, giving-way, walking, stair climbing, running, and twisting. Before the operation, 50% of the patients had moderate to severe pain with daily activities but at follow-up, only 13% had these complaints.

Before the operation, all patients had either given up all athletic activities or had severe limitations with even light recreational activities. At follow-up, 63% were participating in low-impact activities without problems, 6% were participating with symptoms, and 31% were not participating in athletic activities.

Because of the higher failure rate, which was attributed to including patients in this study who had poor-quality posterolateral tissues and prior failed posterolateral procedures, we now recommend the anatomic FCL reconstruction in the majority of cases.


Proximal Advancement Posterolateral Structures

We followed a group of patients who underwent a proximal advancement of the posterolateral structures between 2 to 6 years postoperatively (reference #4). The ACL and/or PCL were also reconstructed in these cases. These patients were carefully selected for this posterolateral operation based on the indications discussed in Part 5 of this course.

We found that 91% of the patients had normal knee stability restored. There were no cases of arthrofibrosis or limitations in knee motion.

There were significant improvements in the scores for pain and activities of daily living. Before the operation, all patients had either given up sports activities or were participating with symptoms and functional limitations. At follow-up, 62% had returned to mostly low-impact activities without symptoms. The other patients did not return due to their knee condition.


Causes of Failure of Posterolateral Operative Procedures

A series of 30 patients were referred to our center after undergoing a total of 57 operations for ruptures of the posterolateral structures (30 first-time and 27 revisions) by other surgeons that did not solve the knee instability and pain (reference #5). We conducted a study to determine to the best of our ability why all of these operations had failed. We found:

  • 77% had a nonanatomic posterolateral procedure. This means that either a graft was used which was not placed in the normal position of the FCL, or that other techniques were used (that did not include grafts) to try to reconstruct these tissues.
  • 37% had bowed legs (varus malalignment) that had not been corrected.
  • 93% had an ACL, PCL, or bi-cruciate ligament rupture that had not been effectively treated.

The results of this study suggest greater emphasis during the first operation for anatomic posterolateral graft reconstruction as discussed in this course surgical, restoration of all ruptured cruciate ligaments, and correction of bowed legs with a high tibial osteotomy.

  1. Noyes, F. R., and Barber-Westin, S. D.: Posterolateral Ligament Knee Femoral-Fibular Reconstruction in Chronic Multi-ligament Unstable Knees. Presented at the Annual Meeting of the American Academy of Orthopaedic Surgeons. New Orleans, March 11, 2010.
  2. Noyes, F. R., and Barber-Westin, S. D.: Posterolateral knee reconstruction with an anatomical bone-patellar tendon-bone reconstruction of the fibular collateral ligament. Am J Sports Med, 35(2): 259-73, 2007.
  3. Noyes, F. R., and Barber-Westin, S. D.: Surgical reconstruction of severe chronic posterolateral complex injuries of the knee using allograft tissues. Am J Sports Med, 23(1): 2-12, 1995.
  4. Noyes, F. R., and Barber-Westin, S. D.: Surgical restoration to treat chronic deficiency of the posterolateral complex and cruciate ligaments of the knee joint. Am J Sports Med, 24(4): 415-26, 1996.
  5. Noyes, F. R.; Barber-Westin, S. D.; and Albright, J. C.: An analysis of the causes of failure in 57 consecutive posterolateral operative procedures. Am J Sports Med, 34(9): 1419-30, 2006.