METHODS: The study involved conducting intradermal injections on four cadavers and participants using a 2 mm length, 34-gauge needle (N-Finders, Inc., South Korea). During the cadaveric study, the polynucleotide prefilled syringe was dyed green, and an anatomist performed dissections, removing only the skin layer. Ultrasonographic observations were carried out to ensure accurate intradermal injection placement.
RESULTS: In all four cadavers, the facial injections at the anterior cheek region were precisely administered intradermally at a 30-degree injection angle. However, the 90-degree injection was found just below the dermal layer upon skin layer removal.
DISCUSSION: The findings suggest that using a 2 mm needle length allows for easy and convenient intradermal injections.
METHODS: Search was performed using a MEDLINE, EMBASE, and Cochrane database, and each of the selected studies was evaluated for methodological quality using a risk of bias (ROB) covering 7 criteria. Clinical and radiological outcomes with more than 5 years of follow-up were evaluated after surgical treatment of DLM. They were analyzed according to the age, follow-up period, kind of surgery, DLM type, and alignment.
RESULTS: Eleven articles (422 DLM cases) were included in the final analysis. Among 7 criteria, 3 criteria showed little ROB in all studies. However, 4 criteria showed some ROB ("Yes" in 63.6% to 81.8%). The minimal follow-up period was 5.5 years (weighted mean follow-up: 9.1 years). Surgical procedures were performed with open or arthroscopic partial central meniscectomy, subtotal meniscectomy, total meniscectomy, or partial meniscectomy with repair. The majority of the studies showed good clinical results. Mild joint space narrowing was reported in the lateral compartment, but none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy could be related to degenerative change. The majority of the complications was osteochondritis dissecans at the lateral femoral condyle (13 cases) and reoperation was performed by osteochondritis dissecans (4 cases), recurrent swelling (2 cases), residual symptom (1 case), stiffness (1 case), and popliteal stenosis (1 case).
CONCLUSIONS: Good clinical results were obtained with surgical treatment of symptomatic DLM. The progression of degenerative change was minimal and none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy were possible risk factors for degenerative changes.
LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.