Hip fractures affect predominately elderly women, resulting in loss of mobility and independence. In Norway alone, there are nearly 10 000 hip fractures each year, of which half are fractures of the femoral neck 1. The terms hip fracture and femoral neck fracture are sometimes used synonymously, however, a fracture of the femoral neck represents a certain type of hip fracture. Trochanteric and subtrochanteric fractures represent other types of hip fractures.
Non-injured hip joint
Undisplaced femoral neck fracture
Displaced femoral neck fracture
Fractures of the femoral neck can be subdivided into displaced and undisplaced fractures dependent on the position of the spherical head of the thighbone in relation to the shaft. An abnormal position with rotation, angulation and loss of alignment is indicative of a displaced fracture, and these fractures are tretated differently from undisplaced fractures.
Animation describing the anatomy of the hip
Femoral neck fractures pose substantial challenges to those affected in terms of pain, reduced quality of life and dependence on caregivers. Although the risk of sustaining a femoral neck fracture no longer seems to increase 2,3,4, changes in demographics with an increasing number of elderly people cause the total number of fractures to rise substantially 5. The situation in Norway is particularly alarming with one of the highest incidences of femoral neck fractures reported worldwide combined with a rapid growth of the older population. In addition to international differences there are also regional differences, and the risk is higher in Oslo compared to Nord-Trøndelag and Sogn og Fjordane. 6,7.
In Norway, femoral neck fractures are treated with arthroplasty or closed reduction and internal fixation. An arthroplasty involves replacement of the femoral neck and head with an artificial implant whereas closed reduction and internal fixation preserves the joint. Closed reduction occurs when the position of the fracture is manipulated to restore anatomical alignments, the fracture is then internally fixated and stabilized using screws or pins.
Treatment with screws
Treatment with hemi-arthroplasty
Animation describing closed reduction and internal fixation
Animation describing hemi-arthroplasty
Choice of treatment
Undisplaced fractures of the femoral neck are generally treated with closed reduction and internal fixation while displaced fractures are treated with arthroplasty. Younger patients with displaced fractures however, are often treated with internal fixation due to higher functional demands and longer life expectancy increasing the risk of future revision arthroplasty. If younger patients are treated with arthroplasty, the head of the thighbone and the socket of the pelvis are both replaced with artificial implants, so called total hip arthroplasty. In contrast, older patients are treated with hemi-arthroplasty only replacing the head of the thighbone.
Arthroplasty and internal fixation have different strength and weaknesses, although the superiority of arthroplasty in terms of better functional results and lower rate of repeat surgery is extensively documented in older patients sustaining displaced fractures 8,9. Importantly, the risk of dislocations and infections is outweighed by the improved results.
In contrast to arthroplasty, infection is not a similarly feared complication associated with internal fixation, but rehabilitation is more demanding and the functional results are poorer the first few years 10,11. A large percentage of patients treated with internal fixation must furthermore undergo repeat surgery 12. If arthroplasty is performed, results are poorer compared to primary arthroplasty 13,14. However, for patients sustaining undisplaced fractures, treatment recommendations are different. The rate of repeat surgery is lower, and internal fixation has generally been recommended as the treatment of choice for this group of patients 15. In terms of mortality, no significant differences have been reported, regardless of displacement 16.
An Historical Retrospect
Professor Julius Nicolaysen
Marius Nygaard Smith-Petersen
Surgical treatment of femoral neck fractures began through the latter part of the nineteenth century. Professor Nicolaysen working at Rikshospitalet in Oslo was an important pioneer during this era, and he was among the first to surgically treat displaced fractures, publishing a material on 13 cases in 1897 (Link, only in Norwegian). Smith-Peterson immigrated to the United States and became professor of orthopedics at Harvard University. He introduced the first modern implant in 1925 in the form of a steel nail, and the Smith-Peterson-nail represented a substantial leap forward in the treatment of femoral neck fractures. The first joint replacements or arthroplasties was performed during the 1940s, and the influential British orthopedic surgeon R.S.Garden expressed his frustration over the increased tendency to treat femoral neck fractures with arthroplasty already in 1964 17. This illustrates that the debate regarding arthroplasty or internal fixation as the treatment of choice has lasted for several decades, a debate that hasn’t been brought to its final conclusion, yet.
Movie describing internal fixation performed in 1941