[Metal staples versus conventional suture for wound closure in total knee arthroplasty]

Surgical incision closure, as well as total joint replacement itself, plays a key role in the overall outcome of an arthroplasty procedure. Uncomplicated wound healing is the essential condition of successful rehabilitation and the patient's return to normal activities. Although there are many innovative suturing techniques which offer advantages, their safety is still being discussed. The aim of this prospective non-blind randomised study was to evaluate wound healing and complications in relation to skin incision closure with either conventional suture or metal staples.

A total of 72 patients, 21 men and 51 women, who underwent a standard primary total knee arthroplasty (TKA) at our department in the period from January till June 2013, were evaluated. They were allocated to two groups by random assignment based on the patient's date of birth (even or odd day of birth). In group 1 (n=39) skin was closed using metal staples (Leukosan Skin Stapler), in group 2 (n=33), conventional continuous Donati suture was used. The groups, previously assessed as independent and comparable in terms of age, gender and BMI, were compared in the following criteria: suturing time, duration of wound drainage, wound healing, complications, resuturing when necessary, and their relation to the body mass index, skin plica thickness and co-morbidities potentially complicating soft tissue healing. The differences were statistically evaluated by parametric and non-parametric tests, i.e., the median test, χ(2)-test, Student's t-test, Fisher's exact test and Pearson's correlation coefficient. The statistical significance of differences was set at a level of 0.05.

A significant difference (p<0.005) between the groups was found in suturing time; the median time for staples was 81 sec in comparison with 290 sec for conventional suture. In both groups, staples or sutures were removed on the 12 th postoperative day and there was no difference in wound drainage (median time, 5 days; p=0.891 for both). Treatment for late discharge was required in two sutured wounds (6.1%) and in three stapled wounds (7.7%). One of the latter was due to early deep wound infection, which later resulted in revision TKA. The groups did not differ in the values of either BMI or plica thickness (Pearson's r).

Views on alternative suture techniques for skin closure in orthopaedic surgery vary. In this study, the use of metal staples or conventional suture is compared between two groups of patients undergoing TKA, i.e., the same type of procedure. The advantage of staples involves a quick and simple application but, as reported, removal may be more painful with staples than with stitches, and much depends on the technique of staple application. The continuous suture technique may produce skin strangulation at wound margins, which will complicate healing. Staples minimise this risk and are therefore commonly used in TKA surgery. However, only very few studies comparing these two suture techniques in TKA patients have been published.

Correctly performed skin suturing by means of metal staples is not associated with a higher complication rate and is therefore a simple, rapid, efficient and economical alternative to the conventional suture technique.