The meniscus is a commonly injured structure in the knee and this injury can occur in any age group. That’s what makes it an area of study for orthopedic surgeons. For quite some time now, surgeons have been able to repair torn or damaged menisci (menisci is plural for meniscus) using minimally invasive arthroscopic techniques.
Ten years ago, a new arthroscopic approach called the all-inside method was introduced. There are several benefits to this technique. First of all, only a few small puncture holes are needed to slip the surgical tools into the joint. No large scars are needed. The back of the knee doesn’t have to be opened to tie the sutures (an inside-out technique). Healing time is shorter.
In this systematic review, results of the all-inside repair technique are compared with outcomes for an inside-out approach. Studies included were confined to patients who had just a meniscus tear without injury to any other part of the knee. And the type of meniscus tear was limited to bucket-handle tears only. A bucket-handle tear refers to a meniscal injury affecting the entire inner rim of the medial meniscus. Medial means closer to the middle of the body.
There are two menisci between the tibia (shinbone) and femur (thighbone) in the knee joint. There is a C-shaped medial meniscus on the inside part of the knee, closest to your other knee. On the lateral side of the knee (side away from the other leg) is a U-shaped lateral meniscus.
In younger people, the meniscus is fairly tough and rubbery, and tears usually occur as a result of a forceful twisting injury. The meniscus grows weaker with age, and meniscal tears can occur in aging adults as the result of fairly minor injuries, even from the up-and-down motion of squatting.
Most studies involve patients who have both a meniscal tear and injury to the anterior cruciate ligament</i (ACL). This review isolated studies that only included patients with isolated medial meniscus bucket-handle tears. With these limitations, they were able to find a total of eight studies (139 patients) using the inside-out suture technique. The combined results of these patients were compared with the combined results from 14 studies including 172 patients with the all-inside repairs.
Results were measured by looking at failure rates, patient report of symptoms and function, operative time, healing rate, and complications. The first thing the study showed was that there weren't very many differences in results using these measures between the two groups. For example, the failure rate was 17 per cent for the inside-out repairs and 19 per cent for the all-inside repairs.
Patients reported similar results in terms of symptoms, knee function, and activity. Complications were fairly equal between the groups, just different for one technique compared with the other. The all-inside approach was more likely to cause local soft tissue irritation with knee swelling. The implants used as sutures for the all-inside repair (arrows, screws, staples, or sutures) were more likely to pull out and shift position (called migration).
Complications with the inside-out repair technique included a higher number of nerve irritations or nerve injuries. In these cases, the tip of suture arrows pressing against the nerve caused pain and had to be removed. These results highlighted one of the main advantages of the all-inside repairs — decreased risk of damage or injury to local blood vessels or nerves (neurovascular structures). Although local nerve injury can occur with the all-inside approach, the number of cases is much smaller compared with the inside-out method.
The final conclusion from this study was that most patients having an arthroscopic medial meniscal repair for an isolated bucket-handle tear have good results. There isn’t any difference between the two different approaches (all-inside versus inside-out) as measured by repair failure, complications, and patient report. There may be some differences in terms of costs and long-term results or differences based on patient age that could be investigated in future studies.