What did the study look at?
Joint cartilage has no blood vessels or nerves, so damaged cartilage is not expected to heal on its own. A common option for small lesions is bone marrow stimulation: the bone layer beneath the cartilage is perforated so that cells from the bone marrow can reach the damaged area. The best known of these methods is microfracture.
Nanofracture is a newer method that uses a 1 mm needle to make deeper, narrower holes. According to the authors, its advantages had been shown in animal models and laboratory studies, but functional results in patients had not. The study aimed to compare the clinical outcomes of the two methods in the knee.
How was it done?
- 42 patients operated on for a knee cartilage lesion were assessed prospectively: 22 received microfracture (Group 1) and 20 received nanofracture (Group 2).
- All had ICRS grade 3–4 lesions; mean lesion size was 3.5 cm².
- Patients with associated problems such as meniscal tears, anterior cruciate ligament injury, malalignment or rheumatic disease were excluded; 84 of 126 screened patients were left out for this reason.
- All procedures were performed arthroscopically by the same surgeon, and both groups followed the same rehabilitation programme (no weight-bearing on the operated side for 6 weeks).
- Outcomes were measured with the Modified Cincinnati and Tegner-Lysholm scores at 6, 12, 24, 36 and 48 months.
What did it find?
- Mean follow-up was 50.8 months in Group 1 and 51.2 months in Group 2. The groups were similar in age, sex, body mass index, lesion size and location.
- Over the follow-up period there was no significant difference between groups in the change in Lysholm (p=0.294) or Cincinnati (p=0.234) scores.
- The only significant between-group differences in the Tegner-Lysholm score were at 6 and 12 months; at 24, 36 and 48 months the differences were not significant.
- In both groups the Lysholm score rose from before surgery (mean about 57–59 preoperatively, 88–90 at 12 months); at 48 months mean values were around 77.
The authors' conclusion
The authors conclude that the functional outcomes of microfracture and nanofracture for knee cartilage lesions do not differ in the mid term, and that long-term results are required.
Limitations
The authors note that the study reports only mid-term outcomes and that results from long-term follow-up need to be shown in further studies.
Reference
Gürsoy S, Simsek ME, Akkaya M, Isik C, Dogan M, Bozkurt M. Micro or nano does not affect the functional outcomes in the midterm follow-up. International Journal of Contemporary Medical Research. 2019;6(2):B1–B5.
DOI: 10.21276/ijcmr.2019.6.2.12
Free full text: International Journal of Contemporary Medical Research
This article summarises a published scientific paper for general information; it does not replace an examination or a personal medical assessment. Please consult your doctor about your symptoms.
