Here’s a unique research dilemma for orthopedic surgeon: how can they study what works best for traumatic knee dislocations when there are so few and the injuries are so different? Most of the time, knee injuries severe enough to cause the joint to dislocate also cause significant soft tissue damage. Multiple ligaments are torn or ruptured requiring surgery. There can also be damage to the nerves and blood vessels in the knee creating even more complications.
Surgeons are searching for the answers to the following questions regarding these patients: 1) How soon should surgery be done? 2) Should they reconstruct the knee fully all at one time or is it better to stage the procedure (i.e., one step at a time)? and 3) How aggressive should rehab be?
A systematic review of the orthopedic literature was done to find some answers. Just as they thought, the authors reported it was difficult to find enough patients with the same combination of knee dislocation and soft tissue injuries to study. There weren’t very many high quality or large studies — mostly single case reports or case series (a group) of patients. It’s difficult to consider the results of those studies evidence on which to base treatment recommendations.
By taking a look at all of the studies from 1950 to 2008, they found 24 studies for a total of 396 knees that qualified for inclusion in this review. Results of treatment were assessed using objective measures such as patients’ return-to-work or return-to-sports status.
Tools used to test for function included the International Knee Documentation Committee (IKDC) subjective knee-evaluation form, the Lysholm scale, Meyers ratings, the Cincinnati knee-rating system, and the Taylor criteria. You can see by the wide range of tests used to measure outcomes that there isn’t even one method used so that comparisons can be made from one study to another. That adds another level of challenge in finding some answers to guide the treatment of traumatic knee dislocations.
It was possible to see a pattern of treatment times. These were divided into acute treatment (first three weeks following the injury), chronic treatment (three or more weeks after injury), and staged treatment. Staged repairs often take place throughout the time periods. The first surgery in a staged procedure is done during the acute phase with follow-up operations during the chronic phase.
Rehabilitation corresponded with these same time periods and could be divided into two major groups: mobilization (early movement) and immobilization (no movement). Data for all patients was put together and analyzed to compare each treatment option with each phase of treatment.
The results were summarized based on measures of joint laxity, joint motion, patient report of satisfaction with results, return-to-work or play, and finally, need for manipulation. Manipulation refers to an operative procedure under anesthesia. The surgeon moves the joint through its full range of motion, gently breaking any adhesions or scar tissue that are keeping the joint from moving and causing severe stiffness and pain.
They found that patients who had acute (early) treatment were more likely to end up with knee instability (joint laxity/looseness) or the opposite: joint stiffness requiring manipulation. Acute treatment followed by immobilization had the worst results. These patients were the least likely to get back-to-work or back-to-athletics.
Patients in the chronic treatment group (treatment three or more weeks after injury) regained their knee joint motion better than the other two groups and were less likely to need a joint manipulation. But results for this group varied and couldn’t be predicted. Staged surgeries seemed to have the best results. Patients who had staged treatment were also more likely to rate their results as good-to-excellent. However, they did have just as much stiffness as the acute group requiring manipulation later.
In terms of the rehabilitation programs, getting patients up and moving rather than putting them in an immobilizing splint or brace didn’t seem to cause joint instability. In fact, in some cases it prevented instability. But it didn’t prevent joint stiffness later.
The most significant findings regarding postoperative treatment involved that acute treatment group. Patients treated surgically in the acute phase (within three weeks of the injury) who also had early mobility had fewer problems with joint stability. This combination (acute treatment with early mobilization) was more likely to get patients back to work. The results suggest that early aggressive rehab after acute treatment may be advised.
The authors state that this was the first systematic review to look at treatment for traumatic knee dislocations. Timing of treatment and post-operative rehab were the two areas of focus. They concluded that even if a review of this type doesn’t find all the answers surgeons need, it does bring to light the need for more research and more reporting of these cases. Eventually with enough data, it might be possible to pool the results and make some firm recommendations based on results rather than on the outcomes of a few small studies or case series.