Femoral shaft medialisation and neck-shaft angle in unstable pertrochanteric femoral fractures.
We analysed the time-dependent mean changes in the femoral neck length, neck-shaft angle and hip offset in a randomised study comprising 48 patients who were treated with the dynamic hip screw (DHS) or the proximal femoral nail (PFN) for an unstable intertrochanteric femoral fracture. As a consequence of fracture compression, the mean post-operative neck length was significantly shorter in patients treated with the DHS. During the first 6 weeks after the operation, a mean decrease of 4.6 degrees was observed in the neck-shaft angle, but there was not a significant difference between the treatment groups. The radiographic measures remained virtually unaffected during the interval from 6 weeks to 4 months in both groups. When the operated hip was compared to the opposite hip, patients who had received the DHS showed significantly greater medialisation of the femoral shaft at 4 months than those treated with the PFN. We thus recommend that unstable intertrochanteric fractures should be initially reduced in a slight valgus position in order to achieve an outcome after healing that is as normal as possible. As a result of differences in operative technique and implant stability, the PFN may be superior to the DHS in retaining the anatomical relations in the hip region in unstable intertrochanteric fractures.
Pajarinen
J
J
Department of Orthopaedics and Traumatology, Helsinki University Central Hospital, P.O. Box 266, 00029 HUS, Helsinki, Finland. jarkko.pajarinen@hus.fi
Lindahl
J
J
Savolainen
V
V
Michelsson
O
O
Hirvensalo
E
E
D000368:Aged; D000369:Aged, 80 and over; D001858:Bone Nails; D001863:Bone Screws; D005260:Female; D006620:Hip Fractures / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods; D011446:Prospective Studies