Arthroscopic retrieval of knee foreign bodies in pediatric: a single-centre experience

The present study was to investigate the clinical features of foreign body (FB) residues in children's knee joints, surgical retrieval, and postoperative function of knee joints.

This retrospective study included a total of 13 children (8 boys and 5 girls; the mean age is 6.69 years old, range from 2 to 16 years old) who underwent retrieval surgery of knee FBs in our hospital. Related clinical factors were recorded and analyzed to find the influence factors of surgical methods and FBs' location change.

The FBs in 11 cases were removed completely by arthroscopy, two cases by open surgery changed from arthroscopy. Besides glass pieces (n = 4, 31%) and wooden splinter (n = 1, 7%), sewing needle fragments were the most common type of knee foreign body (n = 8, 62%). There were two patients with FBs whom open surgery changed from arthroscopy was performed. The FBs of patients with open surgery changed from arthroscopy were more likely to locate in the posterior compartment (p = 0.04), and had a higher interval between injury and surgery than that in patients with arthroscopy (p = 0.01). The location of FBs (all were needle fragments) had changed intra-operatively in three patients, whose mean weight was lower than patients with fixed FBs (p = 0.04). The FB (small glass piece) of one patient was flushed out of the joint during arthroscopy.

Arthroscopic retrieval surgery was an effective procedure to remove the FBs of the children's knee joint. The earlier it is detected, the easier it is to be treated. The location change of FBs should be cautioned in arthroscopic surgery and they are more likely to migrate into the posterior compartment of the knee joint.