We report the clinical and radiological outcome of subcapital osteotomy of the femoral neck in the management of symptomatic femoroacetabular impingement (FAI) resulting from a healed slipped capital femoral epiphysis (SCFE). We believe this is only the second such study in the literature. . We studied eight patients (eight hips) with symptomatic FAI after a moderate to severe healed SCFE. There were six male and two female patients, with a mean age of 17.8 years (13 to 29). . All patients underwent a subcapital intracapsular osteotomy of the femoral neck after surgical hip dislocation and creation of an extended retinacular soft-tissue flap. The mean follow-up was 41 months (20 to 84). Clinical assessment included measurement of range of movement, Harris Hip Score (HHS) and Western Ontario and McMaster Universities Osteoarthritis score (WOMAC). Radiological assessment included pre- and post-operative calculation of the anterior slip angle (ASA) and lateral slip angle (LSA), the anterior offset angle (AOA) and centre head–trochanteric distance (CTD). The mean HHS at final follow-up was 92.5 (85 to 100), and the mean WOMAC scores for pain, stiffness and function were 1.3 (0 to 4), 1.4 (0 to 6) and 3.6 (0 to 19) respectively. There was a statistically significant improvement in all the radiological measurements post-operatively. The mean ASA improved from 36.6° (29° to 44°) to 10.3° (5° to 17°) (p <  0.01). The mean LSA improved from 36.6° (31° to 43°) to 15.4° (8° to 21°) (p < 0.01). The mean AOA decreased from 64.4° (50° to 78°) 32.0° (25° to 39°) post-operatively (p < 0.01). The mean CTD improved from -8.2 mm (-13.8 to +3.1) to +2.8 mm (-7.6 to +11.0) (p < 0.01). Two patients underwent further surgery for nonunion. No patient suffered avascular necrosis of the femoral head. Subcapital osteotomy for patients with a healed SCFE is more challenging than subcapital re-orientation in those with an acute or sub-acute SCFE and an open physis. An effective correction of the deformity, however, can be achieved with relief of symptoms related to impingement. Cite this article: Bone Joint J 2014;96-B:1441–8

Options for the treatment of subcapital femoral neck fractures basically fall into two categories: internal fixation or arthroplasty (either hemiarthroplasty or total hip arthroplasty). Historically, the treatment option has been driven by a diagnosis-related approach (non-displaced neck fractures versus displaced neck fractures). More recently, the traditional paradigm has changed. Instead of a diagnosis-related approach, it has become more of a patient-related approach. Treatment options take in to consideration the patient’s age, functional demands, and individual risk profile. A simple algorithm can be helpful in terms of directing the treatment. Non-displaced fractures, regardless of age of the patient, should be treated with closed reduction and internal fixation. For displaced femoral neck fractures, the treatment differs depending on the age of the patient. The younger patient should be treated with urgent ORIF with the goal of an anatomic reduction. For displaced femoral neck fractures in the elderly, cognitive function should be determined. For those who are cognitively functioning, total hip arthroplasty appears to be the best option. In the cognitively dysfunctional, a bipolar hemiarthroplasty or a total hip arthroplasty with use of larger heads (32 mm or 36 mm) and/or constrained sockets are a viable option

1. Practical experience has shown that subcapital fractures of the femur unite freely if reduction is stable and fixation is secure. 2. Stable reduction is obtained when the muscular and gravitational forces tending to redisplace the fracture are opposed by equal and opposite counterforces, and inherent stability is believed to depend upon the integrity of the flared cortical buttress at the postero-inferior junction of the femoral neck and head. 3. In the stable subcapital fracture a state of equilibrium is reached when the forward and upward thrust of the fixation appliance in the femoral head is opposed by the counterthrust of the closely applied and cleanly broken fragments at the postero-inferior aspect of the fracture. When the postero-inferior cortical buttress is comminuted, inherent stability is lost, lateral rotation deformity recurs and the fixation device is avulsed from the cancellous bone of the head. 4. Stability may be restored by reduction in the "valgus" position, by various forms of osteotomy, by refashioning the fracture fragments or by a postero-inferiorly positioned bone graft. Theoretically, stability may also be obtained by a double lever system of fixation in which an obliquely placed fixation device or bone graft is combined with a horizontally disposed wire, pin, nail or screw crossing it anteriorly. Multilever fixation by three or more threaded wires or pins inserted at different angles and lying in contact at their point of crossing may likewise provide stability. 5. Fixation by two crossed screws has been chosen for clinical trial in 100 displaced subcapital fractures. Imperfect positioning of the screws in seven patients has been followed by early breakdown of reduction and non-union, but satisfactory positioning has been associated with radiological union in fifty patients who have been observed for twelve months or more. 6. Ultimate breakdown in some of these fractures is certain to follow avascular necrosis, and this complication has already been seen in a few patients treated by cross screw fixation more than two years ago. It is also expected that non-union will occur in some of those patients still under observation for less than a year. Even so, these preliminary findings indicate a percentage of union far greater than that obtained by previous methods of treatment, and, although statistically inadequate, they are presented in support of the belief that it should no longer be considered impossible to achieve the same percentage of union in subcapital fractures of the femur as we are accustomed to expect in the treatment of fractures elsewhere. It is not implied, however, that this ideal will be reached merely by the adoption of some form of double or multilever fixation, and much will continue to depend upon the quality of the radiographic services, the precision of reduction and the perfection of operative technique. 7. Every advance in our understanding of what is meant by "perfection of operative technique" lends increasing support to the ultimate truth of Watson-Jones's (1941) dictum: "A perfect result may be expected from a technically perfect operation; an imperfect result is due to imperfect technique." But the simple and foolproof method of fixation which will end the search for technical perfection in the treatment of the displaced subcapital fracture has yet to be evolved, and many questions remain to be answered about this injury. Nevertheless, it is clear that the surgeon should now be prepared to attribute early mechanical failure in the treatment of femoral neck fractures to his own shortcomings, and the temptation to blame capital ischaemia for every disaster should be resisted

We reviewed prospectively, after skeletal maturity, a series of 24 patients (25 hips) with severe acute-on-chronic slipped capital femoral epiphysis which had been treated by subcapital cuneiform osteotomy. Patients were followed up for a mean of 8 years, 3 months (2 years, 5 months to 16 years, 4 months). Bedrest with ‘slings and springs’ had been used for a mean of 22 days (19 to 35) in 22 patients, and bedrest alone in two, before definitive surgery. The Iowa hip score, the Harris hip score and Boyer’s radiological classification for degenerative disease were used. The mean Iowa hip score at follow-up was 93.7 (69 to 100) and the mean Harris hip score 95.6 (78 to 100). Degenerative joint changes were graded as 0 in 19 hips, grade 1 in four and grade 2 in two. The rate of avascular necrosis was 12% (3 of 25) and the rate of chondrolysis was 16% (4 of 25). We conclude that after a period of bed rest with slings and springs for three weeks to gain stability, subcapital cuneiform osteotomy for severe acute-on-chronic slipped capital femoral epiphysis is a satisfactory method of treatment with an acceptable rate of complication

Quantitative polarised light microscopy was applied to sections of unfixed, undecalcified bone taken at operation from patients with two types of proximal femoral fracture, subcapital and trochanteric. Specimens were also taken from the equivalent sites in otherwise normal subjects at autopsy, and from various other sites of traumatic fractures; these two latter groups acted as controls. Analysis of the 57 specimens disclosed changes in the nature of the bone at the site of subcapital fractures, namely the presence of relatively large crystals of hydroxyapatite and a change in the molecular orientation, but not total content, of the acidic proteoglycans of the bone matrix. Our results have confirmed and extended the findings of others on subcapital fractures, and have also shown very similar changes in the trochanteric fractures. It thus appears that the bony changes in the two types of proximal femoral fracture are not as different as has been suggested

We report a prospective study of 198 cases of subcapital fracture of the femur treated by closed reduction and fixation with a sliding compression screw-plate. This was done without regard to the patient's age or the Garden stage of the fracture. Early weight-bearing was encouraged. Of the displaced fractures 23% failed in the first year because of non-union or infection. Of the fractures which united 27% had developed avascular necrosis after three years. Despite this we believe that the sliding compression screw-plate, of proven value in the treatment of intertrochanteric fractures, is also useful for the fixation of subcapital fractures

Between 1999 and 2005, 10 264 patients who had undergone total hip replacement (THR) for subcapital fracture of the hip were compared with 76 520 in whom THR had been performed for other reasons. All the cases were identified through the Swedish Hip Arthroplasty Register. The THRs performed as primary treatment for fracture were also compared with those done after failure of internal fixation. After seven years the rate of revision was higher in THR after fracture (4.4% vs 2.9%). Dislocation and periprosthetic fracture were the most common causes of revision. The risk was higher in men than in women. The type of femoral component and the surgical approach influenced the risk. After correction for gender, type of component and the surgical approach the revision rates were similar in the primary and secondary fracture THR groups. Total hip replacement is therefore a safe method for both the primary and secondary management of fracture of the hip

Articular cartilage from the femoral heads of 27 patients having an arthroplasty for subcapital fracture was studied, and its mechanical and chemical properties compared to those of a group of 33 age-matched macroscopically normal autopsy specimens. Water and proteoglycan contents were measured, as were swelling ability, compressive and tensile strength of the cartilage, and the density of the underlying bone. Cartilage from the fracture specimens had a significantly reduced proteoglycan content, as measured by fixed charge density, and increased swelling ability. These results indicate that this group differs from the "normal" population and care should be taken before they are accepted as control material for studies on osteoarthritic cartilage. Another finding was that bone density was much the same in the fracture and the normal group. This casts some doubt upon the concept that patients who sustain subcapital fractures are more osteoporotic than the average for the same age range

The results of primary total hip arthroplasty for sub-capital femoral neck fracture in previously normal hips are reported. Thirty-seven patients aged 70 or less at the time of surgery were reviewed at an average follow-up of 56 months. Eighteen (49%) had undergone or were awaiting revision surgery. A further four (11%) had definite radiological signs of loosening. Harris hip scores were calculated and correlated well with the results of gait analysis; these suggested that it was the more vigorous patients that were more liable to early failure. Consequently, primary total hip replacement is not recommended for subcapital fractures in the younger patient without pre-existing hip pathology

The management of displaced subcapital fracture of the hip is still controversial because of the high incidence of complications after internal fixation or hemiarthroplasty. To avoid some of these complications we have used primary total hip replacement for independently mobile patients over 65 years of age. A total of 163 cases, operated on over four years, have been reviewed. There were relatively more dislocations after operation for fracture than after total replacement for arthritis, and these were associated with a posterior approach to the hip. Only seven revision operations have been required. Of 57 patients who were interviewed an average of 42 months after replacement, 62% had excellent or good results as assessed by the Harris hip score. All the others had major systemic disease which affected their assessment. This inadequacy of current systems of hip assessment is discussed. It is concluded that total hip replacement is the best management for a selected group of patients with this injury, and that further prospective studies are indicated

This abridged account of a report to the British Medical Research Council describes a long-term investigation of 1,503 subcapital fractures of the femur, almost all of which were treated by reduction and internal fixation. With three exceptions, union occurred in all Garden Stage I and Stage II fractures and in 67% of Stage III and Stage IV fractures, of which only 14-5% were united at six months. In women, late segmental collapse was seen after union had occurred in 16% of Stage I and in 27-6% of Stage III and Stage IV fractures. Delay of up to one week before operation had no significant effect on the incidence of non-union or of late segmental collapse. The incidence of union followed by late segmental collapse was higher in women with normal bone density than in those with osteoporosis. Smith-Petersen nailing was found to be the least effective form of fixation in displaced fractures. The age and physical state of the patient, the accuracy of reduction, and the security of fixation had the greatest influence on union

1. The long-term results in a consecutive series of 323 healed subcapital fractures of the femur show that, with few exceptions, the capital fragment maintains its integrity when the fragments are aligned within the narrow limits of good reduction, but undergoes superior segmental collapse when reduction is poor. 2. The effect of malreduction on the congruity of the hip joint is examined, and a remodelling response to malalignment of the aspherical femoral head in the imperfectly round acetabulum is proposed as an alternative interpretation of the radiological changes now considered to be the result of capital ischaemia

Between December 1982 and June 1986, 98 displaced subcapital femoral neck fractures were treated using the Charnley-Hastings bipolar hemiarthroplasty. Although the patients were elderly, often with associated medical problems, the operation was well tolerated and the mortality at one and six months was 14.4% and 24.5% respectively. Fifty-four hips were reviewed after an average follow-up of 33 months; 64.8% of patients had a good or excellent result. The fair or poor results were seen mainly in patients with poor pre-operative mobility and multiple medical problems. A significant cause of morbidity was dislocation (two interprosthetic) which occurred in six hips. There were two cases of deep sepsis but neither patient was fit for further surgery. There were no cases of acetabular erosion requiring revision surgery

A retrospective study of 200 cases of subcapital fracture of the neck of the femur treated by sliding nail-plate fixation has been carried out. Failure of fixation within three months occurred in forty-two cases (21 per cent). These failures could, in part, be attributed to a combination of the severity of the fracture and various imperfections in technique. The age of the patient and the angle of the nail-plate had no significant effect on the result

1. Ten cases are reported of subcapital fractures of the femoral neck with low fracture-shaft angles treated by wedge osteotomy and fixation by nail-plate. 2. A simple method of osteotomy to increase the fracture-shaft angle is described. 3. In eight fresh fractures bony union was obtained when nailing was followed by immediate osteotomy. 4. The alteration of the bony anatomy does not prejudice further reconstructive surgery should it become necessary

We report a prospective study of the influence of various factors on the six-month mortality of 531 patients with subcapital hip fractures. We performed univariate and multivariate analyses on the 403 patients treated surgically. The most significant predictors of the six-month mortality were dementia, postoperative chest infection, malignant neoplasia, old age and deep-wound infection, in that order. A simple test of mental ability was the most significant prognostic indicator and this test should be included in future studies of the management of hip fractures in the elderly

Ten cases of a complication of Garden screw fixation of subcapital fracture, namely subtrochanteric fracture through the lower screw hole, are presented. Their possible aetiology, prevention and difficulties in management are discussed. It is recommended that, during the insertion of Garden screws, care should be taken to avoid multiple attempts at passing the guide wire. If subtrochanteric fracture occurs internal fixation with a nail plate or screw plate is advised. Ideally the nail or screw should be inserted along the track of one of the existing screws

In a 10-year prospective study, 561 displaced subcapital fractures of the femoral neck in 546 patients were treated with the Hastings bipolar hemiarthroplasty. Within six months of their operations, 148 patients had died. In 322 hips followed up, 243 with adequate serial radiographs separated by more than one year, only 14 (5.6%) showed acetabular erosion. A group of 91 had been reviewed for between three and nine years (mean, 4 years 10 months) and of these, 95% had no pain or slight pain only. Comparison with an earlier series of conventional hemiarthroplasties reported from this institution showed that the clinical results were similar, but that the erosion rate had been halved

One hundred and twenty-seven consecutive patients with displaced subcapital fractures of the femoral neck (Garden Grade III or IV) all under 80 years of age and independently mobile, were randomly allocated to fixation with either double divergent pins or a single sliding screw-plate device. The incidence of non-union and infection in the sliding screw-plate group was significantly higher, and we believe that when internal fixation is considered appropriate multiple pinning should be used. Mobility after treatment was disappointing in about half of the patients, and we feel that internal fixation can only be justified in patients who are physiologically well preserved and who maintain a high level of activity

A prospective randomised trial of surgical treatment for the displaced subcapital femoral fracture in patients of 70 years or more is presented. Two hundred and eighteen patients were randomly allocated into one of three treatment groups: manipulative reduction and internal fixation using Garden screws; Thompson hemiarthroplasty through a posterior (Moore) approach; and Thompson hemiarthroplasty through an anterolateral (McKee) approach. There is no significant difference in the mortality of the internal fixation and posterior arthroplasty groups. Both groups showed a significantly higher mortality than patients operated on through the anterior approach. The technical results of operation were worse in the internally fixed group, with only 40 per cent being satisfactory. Mobilisation was best achieved after the posterior approach. It is concluded that Thompson hemiarthroplasty, using an anterolateral approach, is the safest operation in this group of patients