The purpose of this study was to identify factors
that predict implant cut-out after cephalomedullary nailing of intertrochanteric
and subtrochanteric hip fractures, and to test the significance
of calcar referenced tip-apex distance (CalTAD) as a predictor for
cut-out. We retrospectively reviewed 170 consecutive fractures that had
undergone cephalomedullary nailing. Of these, 77 met the inclusion
criteria of a non-pathological fracture with a minimum of 80 days
radiological follow-up (mean 408 days; 81 days to 4.9 years). The
overall cut-out rate was 13% (10/77). The significant parameters in the univariate analysis were tip-apex
distance (TAD) (p <
0.001), CalTAD (p = 0.001), cervical angle
difference (p = 0.004), and lag screw placement in the anteroposterior
(AP) view (Parker’s ratio index) (p = 0.003). Non-significant parameters
were age (p = 0.325), gender (p = 1.000), fracture side (p = 0.507),
fracture type (AO classification) (p = 0.381), Singh Osteoporosis
Index (p = 0.575), lag screw placement in the lateral view (p =
0.123), and reduction quality (modified Baumgaertner’s method) (p = 0.575).
In the multivariate analysis, CalTAD was the only significant measurement
(p = 0.001). CalTAD had almost perfect inter-observer reliability
(interclass correlation coefficient (ICC) 0.901). Our data provide the first reported clinical evidence that CalTAD
is a predictor of cut-out. The finding of CalTAD as the only significant
parameter in the multivariate analysis, along with the univariate
significance of Parker’s ratio index in the AP view, suggest that
inferior placement of the lag screw is preferable to reduce the
rate of cut-out. Cite this article:
We report three cases of spontaneous healing of aneurysmal bone cysts (ABC). In one case histological material was obtained after resection of the already ossified expansile mass discovered as a lytic lesion seven months previously. In the two other patients, spontaneous ossification of a radiologically presumed ABC in the lytic and expansile phase was observed after nine and seven months respectively. The healed lesions have remained stable at 12, 32, and 36 months respectively. These findings suggest that when the diagnosis can be made with confidence, and the lesion is in a location and at a stage that does not entail any risk of fracture or compression, expectant management should be considered. Our three patients were aged 22, 19 and 18 years, older than usual for developing ABC. This is also true for many of the few other reported cases of spontaneous or almost spontaneous healing and suggests that ABC has a greater tendency to stabilise in older patients.
