CASE 1: Stable fracture treated with screw fixation

Patient

A 93-year-old woman sustained a low-energy fall. She lived with her granddaughter at home and could ambulate independently.

Comorbidities

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  Hypertension

  
  
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  Mild cognitive dysfunction

Treatment and outcome

The patient′s x-rays in the emergency department revealed a right-sided valgus-impacted femoral neck fracture ( Fig 3.9-1a ). This appeared well aligned on the lateral view ( Fig 3.9-1b ). She underwent screw fixation in situ, which was found to be stable under image intensification ( Fig 3.9-1c–d ). She was mobilized and allowed to bear weight, and the fracture showed evidence of radiographic and clinical healing at 3 months ( Fig 3.9-1e ).

Nine months later she had a similar fall and sustained a similar injury on the contralateral side ( Fig 3.9-1f ), despite the use of intravenous bisphosphonate therapy to manage osteoporosis after the first fracture. This was also treated with screw fixation ( Fig 3.9-1g ). Her second fracture also went on to uneventful healing ( Fig 3.9-1h ).

Discussion

This patient sustained sequential bilateral stable femoral neck fractures. Both were treated successfully with internal fixation. The patient was allowed to bear weight as tolerated after both surgeries, which was crucial for early rehabilitation and return to function.

Operative fixation options here included the use of internal fixation or arthroplasty. Unstable fracture patterns have more reoperations when internal fixation is used than stable fracture patterns. Determination of the stability of the fracture can be assessed using x-rays with AP and lateral views. There may be a role for the use of computed tomographic scanning to help in this determination [19]. Another possible option is to use image intensification in the operating room to assess stability with range of motion of the hip. This does require extra operating time as this must be done prior to positioning the patient for either internal fixation or hemiarthroplasty. Two image intensifiers can also help in positioning the screws during surgery.

If internal fixation is chosen, various options exist. It is unclear if screw fixation or sliding hip screw with side plate is the best option [20]. Currently, the results of the trial by fixation using alternative implants for the treatment of hip fractures investigators, which seeks to answer this question, are nearing publication [21]. Arthroplasty, while a longer surgery, may provide better results long term with less reoperations and higher patient satisfaction [18]. Another controversial topic within this case is the prevention of second osteoporotic fractures. The rate of a second fracture is particularly high in female patients with advanced age and multiple comorbidities [22]. The exact pharmacological treatment of osteoporosis in geriatric patients or near the end of life is controversial. Treatments that take time to work may not be worthwhile. Bisphosphonate therapy is thought to be cost-effective in patients up to age of 90 years [23]. Fall prevention strategies and supplementation with calcium and vitamin D are worthwhile. Patients with femoral neck fractures should be assessed and treated for osteoporosis after fracture. Despite treatment with intravenous bisphosphonate, this patient sustained a second fragility fracture.

Key points

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  Stable femoral neck fractures with no displacement or with stable valgus impaction can be treated with internal fixation.

  
  
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  Screws should be carefully positioned in an inverted triangle to give the best chance of fracture healing with internal fixation.

  
  
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  If the fracture is noted to be unstable on evaluation with image intensifier, strong consideration should be given for arthroplasty rather than internal fixation.

CASE 2: Unstable fracture treated with fixation

Patient

A 72-year-old woman with a history of stroke and left-sided weakness. Twenty years earlier, she had sustained a distal femoral fracture treated with a retrograde nail. She was minimally ambulatory getting from bed to chair and always used a walker. The patient fell from a seated position and sustained a displaced femoral neck fracture with x-rays demonstrating a low femoral neck fracture ( Fig 3.9-2a ). The intramedullary rod extended to below the lesser trochanter. After discussion with the patient and family the decision was made to attempt fracture fixation, as arthroplasty would have required removal of the nail.

Treatment and outcome

Fracture fixation was performed using a 4-hole sliding hip screw with side plate to overlap the nail ( Fig 3.9-2b–c ). The fracture was unstable at the time of fixation and a derotation pin was placed during insertion of the hip screw. The pin was removed after screw placement. The bone quality was extremely poor. After surgery, the patient had increasing pain and at 2 weeks the fracture fixation was seen to have slipped with migration of the screw ( Fig 3.9-2d ). Two weeks later the screw had cut out through the head and pain was worse ( Fig 3.9-2e ).

The patient wanted to try to walk again and elected to have the hardware removed with conversion to a hip arthroplasty. During surgery the hip screw was removed and the hip was found to be stiff. The nail was then removed. The bone of the distal femur had grown in to the nail, and some of the intramedullary bone of the distal femur came out with the nail, weakening the distal bone.

During further hip exposure the distal femur fractured ( Fig 3.9–2f ). The intraoperative decision was made to treat the distal femoral fracture with a long locking plate and the femoral head was removed ( Fig 3.9-2g). The distal femoral fracture healed and the patient went on to use a motorized wheelchair for ambulation. At 3 months after surgery, the hip was much less painful and she was satisfied with the result ( Fig 3.9-2h–i ).

Discussion

Decision making is important in the minimally ambulatory patient. In this situation arthroplasty was fraught with difficulty with the in situ hardware and the extremely poor bone stock. Removal of the retrograde femoral nail was difficult, and the unstable nature of the fracture made fixation challenging. While the sliding hip screw was placed with a low tip-apex distance, the bone quality was so poor that fixation was not sufficient. Perhaps initial hip resection or nonoperative care would have led to the same results but with much less morbidity than the two operations that were performed.

Another option for difficult cases with poor bone is the use of cement augmentation. This is not approved for use by the Food and Drug Administration in the United States but is commonly used in Europe [24]. Cement is carefully placed within the femoral head prior to placement of the hip screw. Great care must be taken to prevent cement from entering the joint and if penetration of the femoral head has occurred with the guide wire, cement should not be used.

Key points

Unstable fractures have a high rate of failure with internal fixation. Some patients with complex problems and minimal ambulation may be better treated with hip resection or nonoperative treatment. Older adults with hip fractures have little reserve, and very little margin exists for both operative and medical errors. The best results should be achieved in the first surgery to prevent complications, morbidity, and mortality.