Table 3

Study characteristics for microfracture studies of the ankle

StudyYearStudy designLevel of evidenceCountrySample sizeMale (%)Age (year)Follow-up (months)Follow-up (%)Number of patients completing studySurgeon expertise (as reported in the study manuscript)GRADE
Backus et al462012RetrospectiveIIIUSA6250.032.5 (Range 13–66)Range 6–125333Expert1
Becher et al472010Case seriesIVGermany4556.040 (SD 14)70 (SD 24)8739Expert1
Becher and Thermann482005Prospective case seriesIVGermany3057.041 (Range 20–74)24 (Range 22–27)9729Expert1
Chuckpaiwong et al492008Prognostic case studyIVUSA10570.040.5 (SD 10.6)31.6 (SD 12.1)100105NR1
Cuttica et al502012Retrospective case seriesIVUSA1368.032.9 (SD 11.8)156 (SD 11.8)8511NR1
Doral et al512012RCTITurkey57 (41 With injection; 16 no injection)51.040.5 (SD 13)248649 (unsure losses to each group)NR3
Gobbi et al522006RCTIItaly9/1063.024 (Range 17–28)53 (Range 24–119)1009 patients (10 joints)Expert2
Guney et al532015RCTIIITurkey1643.042.8 (SD 14.7)16.2 (Range 12–24)10016NR2
Guo et al542010Retrospective case seriesIVChina4883.031.8 (SD 10.2)23.9 (Range 12–59)9043NR1
Jung et al552011Case seriesIVSouth Korea2273.040 (Range 20–64)Median 32 (range 18–63)NRNRExpert1
Kuni et al562012Retrospective case seriesIVGermany2255.0Median 31 (range 13–68)24 (NR)10022Expert1
Lee DH et al572012RCTIISouth Korea40 DWB;
41 EWB
79.036 (Range 18–59)DWB 38 (range 24–76); EWB 37 (range 24–74)NRNRNR3
Lee et al582010Case seriesIVSouth Korea3577.035 (Range 17–50)33 (NR)NRNRExpert1
Lee et al592009Case seriesIVSouth Korea19/2075.038 (Range 19–51)12 (NR)10019 patients (20 joints)Expert1
Li et al602014Retrospective case seriesIVChina5864.038.84 (NR)35 (SD 7.3)10058NR1
Park and Lee612015Prospective comparative studyIISouth Korea58 Ch
46 OC
81 Ch
54 OC
22.5 OC (95% CI 19.5 to 25.4); 41.5 Ch (95% CI 38.9 to 44.1) 38.3 OC (95% CI 35.4 to 41.2); 37.6 Ch (95% CI 34.7 to 40.5)100104Expert1
Sallakh622012Case seriesIVEgypt24/2576.038 (Range 18–60)32 (Range 22–44)10024 patients (25 joints)Expert1
Saxena and Eakin632007Case seriesIVUSA2671.036.2 (SD 6.5)32 (Range 24–55)10026Expert1
van Bergen et al642013Case seriesIVThe Netherlands5060.032 (SD 10)144 (Range 96–240)8844Expert1
  • GRADE: 1=very-low-quality evidence; 2=low-quality evidence; 3=medium-quality evidence; 4=high-quality evidence.

  • Ch, chondral; DWB, delayed weight-bearing; EWB, early weight-bearing; GRADE, Grades of Recommendation, Assessment, Development and Evaluation; NR, not reported; OC, osteochondral; RCT, randomised controlled trial.