Transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. 43 patients followed for at least 3 years

We reviewed 48 hips in 43 patients 3-7.1 years (average 4.6 years) after Sugioka transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. The average age at operation was 41 years. Thirty-four patients were men and 9 women. Overall results at the final follow-up were satisfactory in 30 hips (62%). Kaplan-Meier's survivorship was 62% at 3 years and 60% at 5 years postoperatively. Six hips for which the ratio of the intact area of the articular surface on the preoperative lateral radiograph was less than 30% showed further collapse. Five hips were converted to bipolar hemiarthroplasties or total hip arthroplasties. Complications, such as varus deformity, subtrochanteric fracture, and ectopic bone formation, occurred in eight hips. Five of them were operated on in the first 2 years of this series. Three of these five operations had unsatisfactory results. We conclude that satisfactory results can be achieved using this osteotomy by maintaining exact surgical technique and by limiting the surgical indications to hips with an intact area of more than one-third of the entire articular surface on the lateral radiograph of the femoral head.     

Osteonecrosis of the femoral head. Hip salvaging with implantation of a vascularized fibular graft

The authors tried to save the hip joint by implanting a vascularized fibular graft, augmented with cancellous bone, into the curetted core of the femoral head that was affected by aseptic necrosis. Forty of 66 hips were observed for a minimum of 20 months and for as long as 66 months (average, 32 months). Clinical assessment according to the cause and severity of the disease was done using the Harris Hip Score. Twenty-eight hips (70%) were rated excellent, 7 (17.5%) were good, 2 (5%) were fair, and 3 (7.5%) failed and were replaced with an artificial joint. Clinically satisfactory results, including good and excellent, were obtained in 35 hips (87.5%). Radiographic evaluation showed improved appearance of the femoral head core in all 15 patients (37.5%) operated on at a precollapse stage of the disease. In 20 hips, the deformity of the femoral head was unchanged (50%), 2 (5%) became worse, and 3 (7.5%) failed. The number of hips with improved appearance as shown on radiographs and those in which the process was unchanged equaled the number of hips with satisfactory clinical results. These data show that the procedure can induce new bone formation that fuses with the affected subchondral bone, thus preventing the articular surface from collapse. This suggests that vascularized fibular grafting is an excellent alternative for hip salvaging when treating femoral head osteonecrosis.     

Intramedullary versus extramedullary fixation of subtrochanteric fractures. A biomechanical study

We compared two different subtrochanteric fracture fixation techniques, an intramedullary hip screw system (IMHS) and an extramedullary, dual sliding screw-plate system (MSP), to determine relative fixation stability. 6 matched pairs of osteosynthesized osteopenic cadaver femurs were axially loaded to 1000 N with concurrent, simulated abductor forces of 0%, 50%, or 86% of the applied head force. The initial loading sequence was made with uniaxial dynamization--the lag screw of the MSP locked and distal locking of the IMHS nail. Femoral head displacement and medial femoral strain were measured for intact femur controls, after fixation of a 2-part reverse oblique subtrochanteric fracture and finally a 3-part reverse oblique subtrochanteric fracture with a lateral wedge defect. The samples were then loaded at 750 N for 10(4) cycles with both devices uniaxially locked, followed by 10(4) cycles with both devices fully biaxially dynamized (unlocked). For the 2-part subtrochanteric fracture pattern, both devices exhibited similar inferior displacements of the femoral head (average 2.0 mm) and medial femoral strain (approximately 70% of intact). Increasing abductor forces decreased medial compressive strain but did not significantly affect head displacement. For the 3-part fracture model, the MSP demonstrated significantly less inferior displacement of the head (1.6 mm vs. 2.1 mm) and both devices demonstrated significantly decreased medial strain. After cycling, head displacement increased approximately 50% in both devices and medial strain increased slightly. After unlocking and cycling, the MSP group showed significant lateral displacement of the proximal fragment. The IMHS and MSP devices provide similar stability for fixation of 2-part and 3-part reverse oblique subtrochanteric fractures. In a biaxially dynamized, 3-part reverse oblique fracture, displacement of the proximal fragment can occur with the MSP.     

Dual-energy X-ray absorptiometry in osteonecrosis of the femoral head

Osteonecrosis of the hip classically produces a heterogeneous density in the femoral head, although the bone marrow ischemia extends down to the femoral neck and trochanters. Also, bone insufficiency fractures due to diffuse bone loss have been implicated in the genesis of osteonecrosis. OBJECTIVES: To use dual-energy X-ray absorptiometry to quantify the bone changes produced by osteonecrosis of the hip and to compare bone mineral density values in patients with osteonecrosis of the hip and in controls. METHODS: Bone mineral density was measured at the femoral neck (total femoral neck, Ward's triangle, and trochanter), femoral head and lumbar spine using dual-energy X-ray absorptiometry (DPX, L Lunar) in 22 patients with osteonecrosis of the hip and in 22 age- and sex-matched controls. RESULTS: In the patients with osteonecrosis, bone mineral density on the affected side was higher than on the opposite side at the femoral head (+18%), femoral neck (+7%), and Ward's triangle (+6%) and lower at the trochanter (-4%). These differences were most marked at the more advanced end of the osteonecrosis spectrum. As compared to age-specific normative values, the osteonecrosis patients had moderately decreased bone mineral density values at the lumbar spine (-0.53 +/- 1.1 SD or -6 +/- 1.5%) and at the femoral neck on the normal side (-0.9 +/- 1.4 SD or 12 +/- 1.8%). As compared to the controls, bone mineral density was significantly decreased at Ward's triangle (-25%; P: 0.04) and nonsignificantly decreased at the lumbar spine (-4.7%; P: 0.15) and at the femoral neck (-15%; P: 0.09).     

Orthopedic management of osteopetrosis: results of a survey and review of the literature

Osteopetrosis or Albers-Schonberg disease is a rare hereditary disorder of osteoclast function in which resorption of bone is diminished, resulting in abnormally dense bones. The condition is known to occur in at least four recognizable clinical patterns, each of which is variable. The optimal treatment of fractures and of bone deformity in these patients has not previously been made clear. To determine appropriate orthopedic management of the condition, we conducted a survey of the membership of the Pediatric Orthopedic Society of North America. The combined experience of 57 surgeons who treated 79 patients with osteopetrosis was compiled. Four femoral neck fractures treated by closed reduction and internal fixation had a satisfactory result, but three treated nonoperatively developed varus and required osteotomy. A total of 20 hips was treated for coxa vara by various means, none of which was free of complications. Valgus osteotomy, when used as the primary treatment for coxa vara, was the most consistently satisfactory procedure, whereas in situ pinning failed in two of three hips. Fourteen subtrochanteric fractures and 31 other fractures of the femur were treated. Good results were reported with traction or casting or both in the majority of those fractures. Twenty-nine tibia fractures were treated successfully, the majority by nonoperative means. Upper extremity fractures healed well with closed reduction and casting. Vertebral fractures, spondylolysis, and back pain were most frequently treated without surgery.     

Femoral head osteonecrosis after bone marrow transplantation

Thirty-five patients with bilateral osteonecrosis of the femoral head after bone marrow transplantation were reviewed retrospectively. The median age at the time of transplantation was 26 years. The first symptoms occurred within 2 years of transplantation. At presentation, 18 of the patients reported pain in both hips, 17 had symmetric radiographic lesions, and 39 of the hips had collapsed. Medical treatment was indicated initially. At the final examination before surgery (median, 3.5 years), 31 patients had bilateral hip pain, 22 patients had symmetric radiographic lesions, and 56 of the hips had collapsed. Fifty-seven of the hips required surgery, including one open drainage, four core decompressions, six cup arthroplasties, and 46 primary total hip replacements. Six hips (four core decompressions; two cups) later underwent total hip replacement revision, and a deep infection developed in one. By considering the requirement of a total hip replacement as a failure of conservative treatment, the rate of survival of the femoral head was 30% 5 years after the transplant. There was no significant difference between the Ficat grades, except for Grade 0, which showed a higher survival rate. The study of the specific features of the osteonecrosis may lead to the recommendation of primary total hip arthroplasty after failure of the medical treatment.     

Mechanical failure of the intramedullary hip screw in a subtrochanteric femoral fracture

The Gamma nail, an implant specifically designed for intertrochanteric and subtrochanteric femoral fractures, has been criticized for its high risk of secondary shaft fractures. A modified design, the intramedullary hip screw has recently been introduced to correct this complication. We present a case of mechanical failure of this new implant that occurred in a pathological subtrochanteric fracture. The centering sleeve of the implant became loose and migrated while the head screw penetrated the acetabulum. Refixation was successful.     

The reconstruction locked nail for complex fractures of the proximal femur

Thirty-seven patients with 37 proximal femoral fractures were treated with a reconstruction locked femoral nail. There were four ipsilateral intracapsular femoral neck and shaft fractures, two intertrochanteric fractures, 18 intertrochanteric fractures with diaphyseal extension, eight subtrochanteric fractures with involvement of the lesser trochanter, and five subtrochanteric fractures without involvement of the lesser trochanter. The overall union rate was 92%. Twenty-one complications developed in 13 patients (35%) which included three of the four femoral neck and shaft fractures, and six of 18 intertrochanteric fractures with diaphyseal extension. Of the five intertrochanteric fractures with diaphyseal extension in which anatomic reduction was not achieved, four developed a complication. Of the nine proximal screws in nine fractures, which were placed short (below the subchondral bone of the femoral head), six fractures developed a complication. The complications included three nonunions, one delayed union, two leg-length discrepancies of > 2.5 cm, two cases of varus deformity of > 10 degrees, two varus deformities < 10 degrees, four instances of revision surgery including one broken 13-mm nail, four proximal screws that backed out and required removal, two cases of pudendal nerve palsy, and one case of heterotopic ossification. Seven patients developed more than one complication. Eleven of the 13 patients with complications required a second surgery to treat the complication. We conclude that the reconstruction locked femoral nail is not a good choice for ipsilateral intracapsular neck and shaft fractures. Our recommendation is that anatomic reduction should be achieved for all cases using the reconstruction femoral nail, but it is absolutely required when treating the intertrochanteric fracture with diaphyseal extension. Reconstruction femoral nails have a high rate of complication due to the complex nature of the fractures as well as the device.     

Aerial fallout of DDT in southern California

Ender's method of intramedullary fixation of intertrochanteric and subtrochanteric fractures is described. Ender's nail is a pre-bent flexible steel nail with a diameter of 4.5 millimeters. Three to five of these nails are inserted from a small incision proximal to the medial epicondyle of the femur into the medullary canal. They are passed through the femur across the fracture site and into the head of the femur, where they diverage. They are in the lines of force and therefore are not subjected to bending moments. The fracture fixation allows immediate weight-bearing. This method of fixation was used in a series of 203 patients. Their average age was sixty-eight years; the mortality rate was 10.3 per cent. In 3.9 per cent superficial infections occurred, but in no case was there a deep infection involving the bone. Functional return (walking) was achieved in all of the survivors who were able to walk at the time of injury, and there were no nonunions.     

Early recognition of Streptococcus pneumoniae in patients with community-acquired pneumonia

In order to elucidate the cause of osteonecrosis of the femoral head in spontaneously hypertensive rats (SHRs), which resembles the osteonecrosis of Perthes' disease, we observed the three-dimensional structure of vascular casts of the blood vessels feeding the femoral head using both optical and scanning electron microscopes. During the period of 9-15 weeks after birth, when osteonecrosis of the femoral heads in SHRs occurred frequently, the lateral epiphyseal vessels (LEVs), which were the main feeding vessels, entered from the lateral of the femoral heads. Anastomosing branches of LEVs between the epiphysis and the femoral neck were scarce even in the femoral heads showing normal ossification. It seemed that the development of LEVs in SHRs did not proceed normally in this period. Furthermore, remarkable segmental stenosis and the obstruction of LEVs were often recognized near the lateral of the femoral heads. These results suggest that LEVs in growing SHRs have the vascular structure that could cause an interruption of the blood supply to the femoral heads.     

The effect of immediate weightbearing after anterior cruciate ligament reconstruction

Immediate weightbearing has been advocated after anterior cruciate ligament reconstruction and is thought to enhance the return of quadriceps muscle activity and knee extension range of motion without jeopardizing graft integrity. This study examined the effect of immediate weightbearing after anterior cruciate ligament reconstruction on the return of vastus medialis oblique electromyography activity, knee extension range of motion, knee stability, physical examination, Lysholm score, and anterior knee pain. Forty-nine patients (24 men and 25 women) undergoing endoscopic central third patella tendon autograft reconstruction were randomized prospectively into two groups. Group 1 patients underwent immediate weightbearing as tolerated. Group 2 patients were kept nonweightbearing for 2 weeks. All measurements were taken before surgery, 2 weeks after surgery, and between 6 and 14 months (average, 7.3 months) followup. There was no effect of weightbearing on knee extension range of motion or vastus medialis oblique function at followup. In addition, knee stability was not compromised after surgery. Seven of 20 (35%) nonweightbearing patients and only two of 25 (8%) immediate weightbearing patients reported anterior knee pain at followup. Overall, immediate weightbearing did not compromise knee joint stability and resulted in a better outcome with a decreased incidence of anterior knee pain.     

Use of osteonics UHR hemiarthroplasty for fractures of the femoral neck

A clinical and radiographic study of bipolar hip arthroplasties was performed for fractures of the femoral neck. All patients were treated with the Osteonics UHR system. Clinical results were evaluated in 77 patients (77 hips) who were observed for an average of 4.8 years (range, 2-10 years). At the latest followup, 67 (87%) patients were rated as having a good or excellent outcome according to the Hospital for Special Surgery hip rating system. Clinical ratings in patients treated with cementless UHR were similar to or better than those of patients with cemented UHR. Hip dislocation occurred in only 3 (2.3%) patients, in whom the hip joint was reduced by a closed procedure without inducing disassembly of the prosthetic components. None of the patients had definitive acetabular erosion. The motion of the outer head was evaluated radiographically in 63 patients in weightbearing and non-weightbearing conditions, 3 to 108 months after surgery. The relative motion at the 2 sites of articulation of the outer head had stabilized by 3 months after surgery and subsequently remained unchanged. The authors' findings indicate that UHR hemiarthroplasty of the femoral head is a reliable treatment for fractures of the femoral neck.     

Chemical immobilisation of giraffe to facilitate short procedures

OBJECTIVE: To evaluate the effects of dynamization of a sliding hip screw plate on the fixation stability for several types of subtrochanteric fractures. Clinical results of treating reverse oblique fractures occasionally show medialization of the femoral shaft. DESIGN: Two types of plate dynamization were compared using the same test protocol in identically prepared groups of uniform, artificial femurs. METHODS: Sawbones composite femurs (Pacific Research Labs, Vashon, WA) having five orientations of simulated subtrochanteric fractures were used with the Medoff plate (Medpac, Inc., Valencia, CA) either fully dynamized or with the sliding lag screw locked. These specimens were physiologically loaded and cycled and displacements of the proximal femur determined. RESULTS: Significantly more shaft medialization occurred with reverse oblique fracture patterns when the Medoff plate was fully dynamized. CONCLUSION: Clinical treatment of reverse oblique fractures with the Medoff plate should be performed using the lag screw locked and only the plate dynamized.     

Treatment of cutout of a lag screw of a dynamic hip screw in an intertrochanteric fracture

Sixteen consecutive patients with cutout of a lag screw of a dynamic hip screw fixation in an intertrochanteric fracture were treated with reinsertion of a lag screw, bone cement supplementation in the neck-trochanter, and subtrochanteric valgus osteotomy. Postoperatively, patients were permitted to ambulate with protected weight-bearing. Fourteen patients were followed-up for at least 1 year (median 2 years; range 1-3 years), and all had a solid union. The union period took a median of 5 months, with a range of 3-7 months. Usually, union of an intertrochanteric fracture was faster than that of subtrochanteric osteotomy (P < 0.01). There were no complications of wound infection, loss of reduction, cutout of a lag screw, or osteonecrosis of the femoral head. From clinical and theoretical considerations, we conclude that despite cutout of a lag screw of a dynamic hip screw fixation being difficult to treat, out technique still can provide an excellent outcome. Therefore, we strongly recommend its wide use.     

Neuronal death induced by SIN-1 in the presence of superoxide dismutase: protection by cyclic GMP

OBJECTIVES: To test whether femoral ostectomy level, subtrochanteric bone mass removal, and stemsize selection significantly affect stem positioning in canine total hip replacement, and to determine ability of the femoral stem component to restore geometry of the normal femoral head and neck. SAMPLE POPULATION: Femurs from 8 adult mixed-breed canine cadavers. PROCEDURE: Femurs were systematically prepared, using 8 combinations of 3 surgical preparation techniques that included level of ostectomy (cervical isthmus vs lesser trochanter), subtrochanteric bone block removal, and femoral stem size (recommended, undersized). Computer-aided analysis of specimen photographs was used to evaluate femoral head offset and position and variability of femoral stem positioning for each of the preparation combinations. RESULTS: Original femoral head offset and position were reconstructed to within a mean of 0.052 and 0.031 cm, respectively, using an undersized femoral stem after ostectomy at the level of the lesser trochanter. Implantation of an undersized femoral stem after subtrochanteric bone block removal improved ability to centralize the distal tip of the implant and reduce the angle between the femoral diaphyseal and implant axes. Ostectomy at the level of the cervical isthmus tended to force femoral implants into a varus position, and ostectomy at the level of the lesser trochanter tended to force implants into a valgus position. CONCLUSIONS: Geometry of normal canine femurs was most closely reconstructed by implantation of an undersized femoral component after ostectomy at the level of the lesser trochanter. Implantation of an undersized femoral component after subtrochanteric bone block removal resulted in the best alignment and centralization of the stem.     

Avascular osteonecrosis of the acetabulum

OBJECTIVE: To investigate the possible occurrence of osteonecrosis in the acetabulum in patients with non-traumatic necrosis of the femoral head. DESIGN AND PATIENTS: One hundred and seventy-nine patients with non-traumatic femoral head necrosis were assessed by MRI and radiography for the presence of acetabular necrosis. Three criteria were established to differentiate between osteonecrosis and osteoarthritic changes: (1) heterogeneous morphology and irregular contours of the lesion; (2) typical demarcation lines of osteonecrosis; (3) deficient accumulation of intravenous gadolinium in the affected regions. RESULTS: In four patients histological confirmation of acetabular necrosis was obtained. The MR analysis of 22 acetabula (9.5% of those examined) showed changes which suggested osteonecrosis. No cystic lesions were demonstrated in the subchondral bone of any patient. Two cases of acetabular necrosis were found without an ipsilateral femoral head necrosis. In two patients of the 14 who had undergone total hip replacement following necrosis of the femoral head, aseptic loosening of the acetabular component was found. CONCLUSION: The study suggests that acetabular necrosis may be an accompaniment to aseptic necrosis of the femoral head. Further work is required to assess its importance in premature loosening of the acetabular element of total hip arthroplasty.     

Painful knees in older patients: radionuclide diagnosis of possible osteonecrosis with spontaneous resolution

The syndrome of osteonecrosis of the femur at the knee presents as sudden onset of knee pain in elderly patients. It is classically associated with a subchondral radiolucency and a positive radionuclide bone scan. The lesion may progress to collapse of the bone. In this report, twelve cases are described in which the clinical entity of osteonecrosis of the femoral condyle was diagnosed because the patients had a clinical picture identical to that of osteonecrosis and also had positive bone scans. However, roentgenographic changes supposedly diagnostic of the condition were not seen. In twelve patients, arthrotomy was avoided. They became asymptomatic and their bone scans returned to normal in a few months.     

Traumatic osteonecrosis of the femoral head following intracapsular fracture: incidence and earliest radiological features

A sub-capital fracture of the femoral neck is common particularly in the elderly female with non-union occurring in 25% and osteonecrosis in up to 24% of united fractures. Assessment of the viability of the femoral head in the early stages is unreliable and initial diagnosis of osteonecrosis depends on recognition of radiological features. Many reports imply that structural failure of the joint surface is the initial abnormality. 121 patients with a sub-capital fracture have been followed up for at least a year and as long as three and a half years. The incidence of osteonecrosis was 8% in Grade I fractures; 4% in Grade II and 21% and 30% in the more severe Grade III and Grade IV fractures. Of the 24 patients with osteonecrosis, increased radiological density developed in 13 at a time interval of 3 months to 36 months after the fracture with a mean time of 10 months and seven subsequently developed structural failure. Eleven patients developed structural failure as an initial feature at a time interval of 5 months to 24 months with a mean of 13 months. From this it is clear that either an absolute increase in radiographic density or structural failure are the earliest radiological features. Good quality radiographs, clearly demonstrating trabecular detail, are essential for the recognition of osteonecrosis.     

Influence of the volume of osteonecrosis on the outcome of core decompression of the femoral head

OBJECTIVES: To assess the outcome of core decompression in the treatment of osteonecrosis of the femoral head related to the volume of necrotic bone measured according to a previously reported method. METHODS: Twenty hips corresponding to strictly Ficat stage II underwent magnetic resonance imaging and the volume of necrotic bone was expressed as a percentage of the volume of the entire head measured on each slice. All hips underwent core decompression and the outcome was evaluated at 24 months. The primary evaluation criterion was radiological appearance: the outcome was considered as good if the hip remained stage II and poor if the disease progressed. RESULTS: Twenty four months after core decompression, half the cases remained stable and in half the disease had progressed. Outcome seemed to be related to the volume of necrotic bone (average 22% in the good outcome group versus 45% in the poor outcome group (p = 0.0051)) and was independent of risk factors, age, and histological type. CONCLUSIONS: The volume of necrotic bone should be taken into account in the evaluation of any treatment, bearing in mind that in more than one third of cases this volume will probably decrease, especially at the beginning of the disease process.     

Topological studies of the amino terminal modules of vitamin K-dependent protein S using monoclonal antibody epitope mapping and molecular modeling

Neglected fractures of the femoral neck, common in young adults in underdeveloped countries, may be complicated by nonunion or avascular necrosis (AVN). We treated 52 cases by open reduction, fixation by compression screw and a free fibular graft. The mean delay between injury and operation was 5.1 months. Of 40 fractures assessed at a mean of 58.8 months (24 to 153), 38 were found to be united and two, owing to surgical errors, were not. Seven of eight heads which were avascular before operation revascularised without collapse, while seven others developed AVN after the procedure. At the last follow-up considerable collapse was apparent in five femoral heads, and 11 hips had developed coxa vara. The fibular graft had fractured in four cases. The hip had been penetrated by the screw in six cases and by the graft in three. Hip function was excellent in seven patients, good in 21 and fair in seven. Five patients had poor results. Incorporation of the fibular graft was seen after four years: in many cases the graft had been almost completely resorbed. We recommend this procedure for the treatment of neglected fractures of the neck of the femur in young adults to reduce resorption of the neck, AVN and nonunion.