To observe the clinical efficacy of platelet rich plasma (PRP) injection in the treatment of chronic meniscus injury.

From January 2016 to October 2017, a total of 35 patients with chronic meniscus injury, which courses were more than 6 months, were treated with PRP injection in Shaoguan Hospital Affiliated to Southern Medical University. Their knee joints were immobilized for three weeks after the first injection and followed up for three to six months. Lysholm score, visual analogue pain score (VAS), meniscus rotation test (McMurray test), Stoller injury grading of MR images were used to evaluate the efficacy. The incidence of complications was also observed. Lysholm score and visual analogue pain score (VAS) were analyzed by variance analysis of repeated measurements. The counting data of McMurray test and MRI image were analyzed by chi-square test.

There were 35 patients with 37 knees and 47 meniscuses, aged from 24 to 71 years, (56±13)years on average. Course of disease were six to 112 months, average (48±33) months. The Lysholm knee score was (65.1±4.8), (68.8±5.1), (71.6±4.8), (72.5±4.9)respectively before treatment, and one month, two months, three months after the first injection; the difference was statistically significant(F=1 968.5, P <0.01). The VAS scores of knee joint were (4.3±0.9), (3.9±0.4), (2.9±0.6)and (2.4±0.8)respectively. The difference was statistically significant (F=72.2, P <0.01). As to frequency of positive, suspicious positive and negative knee joint McMurray test, the cases were 41, six and zero before the treatment; and six, 11, 30 cases after the treatment respectively. the difference was statistically significant(χ²=57.53, P< 0.01). In addition, the Stoller-graduation, stage zero, I, II and III were zero, four, 36, and seven cases respectively before the treatment; six, 26, 11, and four cases respectively after the treatment at three months; the difference was statistically significant(χ²=36.25, P < 0.01). The total effective rate of meniscus chronic injury showed by MRI was 74.47% (35/47). Although there were 10.81% (4/37) knees accompanying with increment of joint effusion showing in MRI, but without special discomfort to patients; the incidence of deep pain was 8.51% (4/47) after PRP injection, which was relieved by heat treatment. No needle injecting tract infection was observed.

PRP treatment can promote the healing of knee meniscus chronic injury, relieve pain, improve symptoms, improve the quality of life, which has an excellent therapeutic effect; complications should be avoided.