Table 5. Last Follow-up Results of Each Studies.
| Study | Definition of failure | Union rate | Cutout or collapse | Nonunion | Reoperation |
|---|---|---|---|---|---|
| Watson et al.7) (2016) | Failure of fixation was defined as collapse of the fracture and movement of the position of the lag screw in the femoral head, or nonunion of the fracture (no sign of healing radiographically or clinically at 6 months postoperatively). | 5/11 | 5/11 | 1/11 | 3-arthroplasty 1-refuse 1-expire |
| TasyIkan et al.9) (2015) | Not mentioned. | 28/28 | 0 | 0 | 0 |
| Hu et al.8) (2013) | Not mentioned. | 28/28 | 0 | 0 | 0 |
| Massoud3) (2010) | Technical failures were defined as lag screw penetration or cut-out of the femoral head, excessive displacement, e.g., femoral shaft medialization, implant breakage or loosening, intra or postoperative femoral shaft fracture or non-union. Lag screw migration without femoral head penetration or cut-out was not regarded as a technical failure. Downward displacement of the proximal fragment without cut-outs or DRS (alone) penetration of the femoral head were not considered technical failures. | 13/13 | 0 | 0 | 0 |
| Su et al.11) (2006) | Fracture collapse was defined as the length of the protrusion of the compression screw from the lateral edge of the barrel relative to the entire length of the lag screw. | 24/28 | 21/28 | 1/28 | 2-hemiarthroplasty 1-implant removal 1-bone graft with screw fixation |
| Chen et al.1) (2008) | Not mentioned. | 263/269 | 2/269 | 4/269 | 4-bone graft with DHS change 2 cutout->THA |
| Saarenpää et al.10) (2002) | Not mentioned. | 16/19 | 1/19-cancellous screw cutout | 2/19-cancellous screw | 1-THA 1-remove 1-girdle stone |
| Kuokkanen13) (1991) | Not mentioned. | 5/6 | 0 | 1/6-infective nonunion | Not mentioned. |
| Davis et al.12) (1990) | Not mentioned. | 7/9 | 2/9 | 0 | Not mentioned. |
| Kweon et al.14) (2017) | Not mentioned. | 15/15 | 0 | 0 | 0 |
| Lee et al.15) (2018) | Fixation failure was defined as reoperation, such as conversion to hip arthroplasty. To determine a collapse of fracture site, the sliding distance of fracture site through hip screw or blade was measured, and a collapse of more than 5 mm was defined as collapse of fracture site. | 63/69 | 6/69 (cutout), 18/69 (collapse) | Not mentioned. | 6-THA |
| Guo et al.16) (2019) | The patients were monitored for complications, such as femoral neck shortening, screw protrusion, screw cutout, nonunion (defined as a fracture with no sign of healing radiographically or clinically at 12 months postoperatively), and avascular necrosis. | 14/14 | 0 | 0 | 0 |
| Wang et al.17) (2019) | The major postoperative complications were identified as cut-out/cut-through, hardware-related femoral fracture, nonunion of the fracture, movement of the position of the lag screw in the femoral head, and varus development as a result of collapse. | 52/52 | 0 | 0 | 0 |
| Kim et al.18) (2020) | Not mentioned. | Not mentioned. | 3/67 (CMN group) | Not mentioned. | 5 (no mentions about reoperation method) |
| Yoo et al.19) (2019) | Cut-out was defined as penetration through the femoral head that was visible on X-ray, while cut-through was defined as the perforation of the femoral head from centric movement and without lateral movement by the lag screw. Significant sliding of the lag screw was defined arbitrarily by the authors, as an irritation sign due to the prominent lateral impingement without deep or superficial infection, as a lag screw sliding distance ≥10 mm in the plain X-ray or the removal of the lag screw due to one or both reasons. The excessive angular change was also arbitrarily defined as 10。or more. | 57/60 in ITST nail, 53/57 in PFNA, 67/68 in Gamma 3 CMN | 3/60 in ITST nail, 4/57 in PFNA, 1/68 in Gamma 3 CMN | Not mentioned. | Not mentioned. |
DRS: derotational screw, DHS: dynamic hip screw, THA: total hip arthroplasty, CMN: cephalomedullary nail, ITST: intertrochanteric/subtrochanteric, PFNA: proximal femoral nail antirotation.