Matthew E. Oetgen and Michael R. Baumgaertner
DEFINITION
Peritrochanteric hip fractures are defined as extracapsular hip fractures, always involving the trochanter and frequently with extension into the subtrochanteric region.
These fractures occur after falls in a substantial number of elderly people (estimated incidence of 250,000 fractures per year) and represent a growing percentage of healthcare expenditures annually.
These fractures require operative intervention to achieve stable fracture fixation to allow immediate patient mobilization.
ANATOMY
The intertrochanteric region of the hip is notable for the anatomic transition from the femoral neck to the femoral shaft.
The angle subtended by the femoral neck and long axis of the femoral shaft in the coronal plane (the neck–shaft angle) is usually between 120 and 135 degrees in adults.
Studies have shown that this angle tends to decrease with age.
The average femoral neck is anteverted between 10 and 15 degrees (range 0 to 50 degrees) and slightly translated anteriorly (5 to 8 mm) from the axis of the femoral shaft.14
The peritrochanteric region of the femur is composed of multiple thickenings of trabecular bone distributed in compressive and tensile groups.4
The thickest and most structural are the primary compressive trabeculae located along the posterior medial aspect of the femoral neck and shaft, also known as the calcar.
Multiple muscle groups attach to this region of the femur.
Iliopsoas: attaches to the lesser trochanter and exerts a flexion and external rotation force to the hip
Abductors and short external rotators: attach to the greater trochanter
Adductors: attach to the femoral shaft distal to the peritrochanteric region
The blood supply to the peritrochanteric region of the femur is rich and abundant. The medial and lateral femoral circumflex arteries supply the cancellous bone of the trochanteric region through muscle attachments at the vastus origin and the insertion of the gluteus medius.
PATHOGENESIS
In the elderly population most peritrochanteric fractures are caused by a fall onto the lateral aspect of the hip, whereas highenergy trauma produces these fractures in younger individuals.
Numerous factors, such as structurally weak bone, less subcutaneous padding, and slowed protective reflexes, lead to increased forces on the hip with falls in the elderly population.
Pathologic lesions in the peritrochanteric region are not uncommon and may lead to pathologic fractures after relatively minor trauma.
NATURAL HISTORY
Almost all peritrochanteric hip fractures will heal without intervention. However, owing to the pull of the musculature in this region, the fracture will heal in gross malalignment, leading to subsequent functional limitations.16
Early operative intervention of these fractures is undertaken to ensure fracture union in an anatomic alignment.
PATIENT HISTORY AND PHYSICAL FINDINGS
It is important to elicit the cause of the patient's fall, as many falls in the elderly population that result in hip fractures are due to medical comorbidities.
Complaints of hip pain before falling may indicate a preexisting pathologic process that requires further evaluation.
A thorough global musculoskeletal examination of the patient is necessary because of the high incidence of associated fractures (especially of the wrist and proximal humerus) in the elderly population sustaining hip fractures from simple falls.
Examination of the soft tissue overlying the lateral hip, sacrum, and heels is necessary to ensure that no pressure ulcers or abrasions have occurred in these areas.
The classic physical finding in a patient with a peritrochanteric hip fracture is a short, externally rotated affected extremity.
Patients may have associated musculoskeletal injuries that are not discovered until examined because of the distracting hip injury.
Hip rotation assessment: Because of the muscular attachments and gravity, the lower extremity tends to rest externally rotated with a peritrochanteric hip fracture.
Passive log-rolling of the leg will elicit pain (particularly with internal rotation, which tightens the hip capsule and causes pain due to the hemarthrosis). This may be an especially helpful finding in occult hip fractures with no obvious fracture deformity.
IMAGING AND OTHER DIAGNOSTIC STUDIES
Plain radiographs consisting of an anteroposterior (AP) pelvis and cross-table lateral of the injured hip should be obtained initially.
A traction radiograph (radiograph taken with gentle manual traction and internal rotation of the leg) will provide more information on the fracture pattern and will allow a better comparison to the uninjured hip (FIG 1A,B).
A fine-cut (2-mm) CT scan with reconstruction images (sagittal and coronal) set to bone windows may help assess the fracture when ipsilateral femoral neck or other fractures are suspected.
MRI is the modality of choice to assess for the presence of an occult peritrochanteric hip fracture in the setting of normal radiographs (FIG 1C).
FIG 1 • A. AP radiograph of an OTA 31-A1 peritrochanteric hip fracture. B. Traction radiograph; note the reduction seen with traction. C. MRI scan of a painful right hip showing an occult peritrochanteric fracture (arrow) not seen on plain radiographs.
DIFFERENTIAL DIAGNOSIS
Femoral neck fracture
Femoral shaft fracture
Greater trochanter fracture
Septic hip
Lateral compression-type pelvic fracture, with pubic rami fractures
NONOPERATIVE MANAGEMENT
Early operative management of peritrochanteric fractures is associated with decreased patient morbidity and improved patient function compared to nonoperative management.
Relative indications for nonoperative management include nonambulatory or demented patients with little pain, patients with active sepsis, patients with skin breakdown around the surgical site, and patients with severe and irreversible medical comorbidities precluding operative intervention.
Nonoperative management consists of two regimens.
Early mobilization
No attempt at axial realignment
Used for nonambulatory patients and consists of pain control and early mobilization out of bed to chair as tolerated to avoid systemic complications of recumbency
Traction
Attempted anatomic realignment with nonoperative management for ambulatory patients
Balanced traction for 8 to 12 weeks, with serial radiographs to assess healing
Progressive weight bearing as the fracture shows signs of healing
SURGICAL MANAGEMENT
Once surgical management is chosen, the timing of intervention becomes important.
The balance between medical optimization and early operative management in this mostly elderly patient population is delicate.
Although a recent study of more than 2600 patients found that a delay in surgery of up to 4 days did not increase patient mortality up to 1 year postoperatively, most studies suggest that delays of more than 2 days may increase patient mortality postoperatively.11,17
Preoperative Planning
Radiographs are reviewed to determine the fracture pattern.
We find the AO/OTA fracture classification system to be useful and reliable for these fractures. It is divided into groups based on fracture geometry (FIG 2):
Group 1 has a single fracture line extending to the medial cortex.
Group 2 has more than one fracture line extending to the medial cortex.
Group 3 has a fracture geometry that runs in a more transverse or reverse oblique pattern, with the fracture line exiting the lateral cortex below the vastus ridge.
Implant selection for fracture fixation should be guided based on fracture pattern and patient age.
OTA 31-A1-type fractures have been shown to be fixed with reliably good results using either a sliding hip screw or intramedullary device.
OTA 31-A2-type fractures have been shown to be amenable to treatment with either side plate and screw devices or intramedullary devices.
Recent studies have shown improved patient outcomes and better maintenance of fracture alignment with the use of intramedullary devices in this type of fracture.12,15
OTA 31-A3-type fractures have been shown to be treated best with intramedullary devices or blade plates.
Sliding hip screw devices are contraindicated in these fractures because of the high incidence of implant failure.6
In a meta-analysis, intramedullary implants were found to have a lower failure rate than blade plates when used to treat this type of fracture pattern and should be considered the implant of choice for the elderly patient.6
Preservation of bone stock in the proximal femur is an important consideration in young patients with this fracture pattern.
FIG 2 • classification of proximal femur fractures.
A fixed-angle plate (such as a 95-degree blade plate or locked plate), as well as a reconstruction-type nail with a small proximal diameter, will allow for stable fracture fixation, along with preserved proximal femoral bone stock, which is helpful in cases necessitating later revision open reduction and internal fixation.
The neck–shaft angle of the nonfractured femur should be measured preoperatively to estimate the reduction to be achieved (FIG 3).
Preoperative planning is vital for a satisfactory outcome when a peritrochanteric fracture is fixed with a blade plate.
Multiple views of the nonfractured, contralateral hip and femur, as well as multiple traction views of the fractured hip, are required to properly plan the surgical sequence for this type of fixation.
Positioning
When fixing a peritrochanteric fracture with a sliding hip screw device, the patient is positioned on a well-padded fracture table, with the nonfractured leg carefully positioned in flexion and external rotation in a well leg holder. Alternatively, the patient may be placed in the “scissor” position, with the nonfractured leg extended and supported with a boot. This position is helpful in some patients (eg, obesity, stiff contralateral hip, bilateral injuries) who may not be able to flex and externally rotate the contralateral hip to enable use of a well leg holder.
FIG 3 • AP pelvis radiograph. The neck–shaft angle has been drawn on the nonfractured extremity.
This facilitates access by the fluoroscopic C-arm to the fractured hip (FIG 4A).
We prefer to secure the affected foot to a well-padded heel cup with tape, leaving the posteromedial neurovascular bundle uncompromised. The foot is then dorsiflexed and secured against a well-padded metatarsal bar to lock the transverse tarsal joint and allow strong traction and rotational forces to be transmitted to the fracture (FIG 4B).
Alternatively, if the fracture is to be fixed with a fixed-angle plate, the patient is placed on a completely radiolucent flat-top table. The affected hip is bumped up at a 20- to 30-degree angle and the leg is draped free.
The scissors position is another alternative position for fixation of a peritrochanteric hip fracture (FIG 4C). The patient is placed supine on a traction table and both feet are secured in traction boots. The noninjured leg is then extended to allow a lateral radiograph of the injured hip to be obtained with relative ease.
Some muscular patients may require skeletal traction of the affected leg through the distal femur or proximal tibia to provide adequate fracture length and alignment.
Approach
Because of the muscular forces exerted on the fracture fragments associated with peritrochanteric hip fractures, perfect anatomic reduction of the fracture is close to impossible with indirect methods, especially in the lateral plane, which is often the most difficult plane to control.
Studies have shown, however, that absolute anatomic reduction of all fragments of these fractures is not necessary for a satisfactory functional outcome.13
The primary goal of reduction of peritrochanteric hip fractures is to re-establish a normal anatomic alignment between the proximal head and neck fragment and the distal femoral shaft in the anteroposterior, lateral, and rotational planes.
A lateral approach to the proximal femur is the preferred approach for open reduction and internal fixation of peritrochanteric femur fractures.
FIG 4 • A. Patient positioned on fracture table. B. Extremity secured with heel cup and metatarsal bar to facilitate manipulation. C. Patient positioned on fracture table in the scissor position.
TECHNIQUES
INCISION
The incision is centered over the lateral aspect of the femur. It is started proximally at the palpable vastus ridge for sliding hip screw devices and just proximal to the tip of the greater trochanter for fixed-angle plates.
The distal extent of the incision is made long enough to allow application of the plate.
The incision is carried through the fascia lata, avoiding the tensor muscle proximally and anteriorly. The vastus lateralis fascia and muscle is incised longitudinally 2 to 3 cm anterior to the linea aspera and retracted anteriorly. Care is taken to identify and control any perforating vessels supplying the vastus lateralis muscle.
Proximally, the origin of the vastus lateralis is sharply released off the vastus ridge to allow atraumatic anterior retraction of the muscle, to facilitate lateral femoral shaft exposure.
Care should be taken to avoid any medial shaft dissection to maintain the vasculature to the fracture zone.
FRACTURE REDUCTION
With the patient accurately positioned on the fracture table, the fracture is initially reduced in the anteroposterior plane with axial traction to re-establish fracture length and partially correct the varus malalignment (TECH FIG 1).
Abduction of the leg usually corrects the final varus malalignment and establishes the normal neck–shaft angle.
Internal rotation of the distal fragment usually corrects the external rotation deformity and will align the femoral neck parallel to the floor to assist in eventual guide pin insertion, but this must be confirmed under fluoroscopy.
In some instances, external rotation of the proximal fragment is necessary to achieve reduction of the rotational deformity.
Fracture reduction is next checked in the lateral plane. These fractures often display an apex-posterior angulation. This can be corrected by placing a crutch under the femoral shaft for support. Alternatively, some fracture tables have padded attachments to support the thigh.
Fracture reduction is reassessed in both the anteroposterior and lateral planes and checked for fracture displacement, neck–shaft angle, neck anteversion, rotation, and femoral shaft sag, with a goal of obtaining a nearanatomic reduction in all of these planes (normal or slight valgus reduction, less than 20 degrees of angulation on the lateral radiograph, and less than 4 mm of fracture displacement).1
If a near-anatomic closed reduction cannot be obtained, a formal open reduction is necessary.
TECH FIG 1 • Fracture reduction. A. Preoperative peritrochanteric fracture. B. Position of the fracture after longitudinal traction. C. Position of the fracture after longitudinal traction and abduction applied. D. Position of the fracture after longitudinal traction, abduction, and internal rotation applied. E. Posterior fracture sag. F. Position of the fracture after longitudinal traction, abduction, internal rotation, and flexion force applied with a crutch under the leg. G. Intraoperative picture of crutch placed under distal fragment.
GUIDE PIN POSITIONING FOR SLIDING HIP SCREW AND FRACTURE PREPARATION
The entrance point for the guide pin is selected once exposure of the lateral femoral cortex is completed.
The entrance for a 135-degree plate is typically 2 cm below the vastus ridge, opposite the midpoint of the lesser trochanter, at the level of the femoral insertion of the gluteus maximus tendon (TECH FIG 2).
The entrance point for the guide pin is adjusted 1 cm proximal (for lower-angled devices) or distal (for higher-angled devices) from the 135-degree starting point for every 5-degree adjustment in the measured neck–shaft angle.
The femoral anteversion can be estimated by advancing a free guide pin by hand up the anterior femoral neck and securing it in the anterior aspect of the femoral head.
The correct-angled guide is placed at the guide pin insertion site, centered in the anteroposterior plane on the femoral shaft and seated flush to the lateral cortex.
The guide pin is advanced under fluoroscopic guidance, in both the anteroposterior and lateral views, to ensure central placement in the femoral head.
If the pin is not centered in the head on both views, it must be removed and adjusted.
The fracture reduction should be reassessed and the guide adjusted to ensure that central guide pin placement is obtained.
The guide pin is inserted to within 5 mm of the joint line in both the anteroposterior and lateral projections.
The interosseous length of the guide pin is measured with the ruler provided in the instrument set.
Care must be taken when deciding on a lag screw length, especially in highly unstable fractures reduced with a substantial amount of traction. This traction can cause fragment distraction and overestimation of lag screw length, which will be noticed when traction is eventually released.
The guidewire is then advanced into the subchondral bone to ensure stability during reaming.
A second guide pin can then be advanced into the femoral head proximal to the original guide pin in unstable fractures or in fractures that are reduced in anatomic alignment using excessive traction.
TECH FIG 2 • Guide pin positioning and fracture preparation. A. Radiograph showing position of guide pin at the level of the lesser trochanter, just below the vastus ridge. B. Angled guide and guide pin inserted parallel to guide pin, showing femoral anteversion. C. Fluoroscopic image showing anteversion pin and inserted guide pin. D. Guide pin advanced into center of the femoral head in the AP projection. E. Guide pin advanced into center of the femoral head in the lateral projection. F. Triple reamer.
This pin acts as a derotational pin to ensure that the proximal neck and head fragment does not rotate with reaming and screw insertion.
A triple reamer is used to prepare the channel in the lateral cortex, neck, and head for the lag screw and side plate barrel.
The reamer is set to 5 mm less than the measured lag screw length to ensure that the subchondral bone in the femoral head is not violated during reaming.
The triple reamer is then advanced and withdrawn under fluoroscopic guidance, ensuring that the guide pin is not inadvertently advanced into the pelvis, the channel is reamed to its proper length, and the guide pin is not withdrawn with the reamer.
Occasionally the intact lateral wall of the proximal femur may be fractured by the triple reamer. If this occurs, the fracture is essentially converted into a transverse or reverse oblique pattern, and excessive fracture collapse will occur if it is fixed with a simple sliding hip screw. In these cases, the proximal lateral wall may be buttressed with the addition of a trochanteric plate in conjunction with a sliding hip screw or conversion to an intramedullary device for fracture fixation.
IMPLANT INSERTION
A two- to four-hole side plate is usually chosen for fixation (TECH FIG 3).
Multiple clinical and cadaveric studies have shown no difference in the strength of implant fixation with side plates with more than four holes.3,9
The implant is set up according to the manufacturer's specifications.
The cannulated lag screw is then inserted over the guide pin with a centering sleeve to ensure proper positioning. Careful sizing of the lag screw is required, as noted earlier, to ensure that fracture compression does not lead to excessive screw length and lateral hardware prominence.
Fluoroscopy and manual fracture palpation is used to ensure that the fracture is not displaced (rotated) while the lag screw is inserted.
If the fracture is displaced by the insertion of the lag screw, it is removed, the channel is tapped, and the lag screw is reinserted.
Peritrochanteric fractures of the right hip tend to displace to an apex-posterior angulation with lag screw insertion, whereas left hip fractures tend to displace to an apex-anterior angulation owing to the anatomic configuration and subsequent tensioning of the hip capsule with screw insertion.
TECH FIG 3 • Implant insertion. A. Lag screw and side plate on inserter. B. Placement of side plate. C. Implant in place. D. Traction released. E. Fracture after compression.
With the lag screw inserted to the desired depth within the femoral head on the anteroposterior and lateral fluoroscopic projection, its relation to the lateral cortex is checked to ensure proper length.
The side plate is then slid over the lag screw so it is seated on the lateral cortex, and the guide pin (and derotational pin if used) is removed.
Traction is released at this point to allow slight impaction of the fracture in the axial plane.
Cortical screws are inserted to secure the plate to the femoral shaft in the usual manner.
A compression screw is then inserted into the barrel of the lag screw and tightened to compress the fracture in the plane of the lag screw, under fluoroscopic guidance.
With the compression of the fracture complete, the alignment and implant position are checked once again with fluoroscopy.
BLADE PLATE INSERTION
With the lateral femur and trochanteric block exposed, a soft tissue-sparing reduction of the trochanteric block to the proximal femur is secured with pointed bone clamps and K-wires or small lag screws as needed (TECH FIG 4).
Guide pins are then introduced into this reconstructed segment to facilitate proper seating of the chisel for the blade plate.
The first pin is placed anterior to the femoral neck and secured into the anterior femoral head to demonstrate the femoral anteversion.
The second pin is placed with the use of an angled guide, fluoroscopy, or both near the tip of the greater trochanter and directed into the femoral head at a 90-degree angle to the femoral shaft once the fracture has been reduced and the neck–shaft angle restored.
The chisel is inserted parallel to the two guide pins, just distal to the second pin. Care must be taken to maintain the correct alignment of the chisel with the shaft of the femur because this determines the flexion-extension of the fracture, which is fixed once the blade plate is inserted.
The chisel is aimed to pass through the center of the neck and seat in the inferior portion of the femoral head. Because of the anterior translation of the femoral head on the shaft, the insertion site is in the anterior half of the trochanter.
The position of the chisel should be constantly checked with fluoroscopy before and during its insertion.
The chisel is carefully removed and the appropriatelength blade plate is inserted and gently seated into the proximal fragment.
The insertion should be frequently checked with biplanar fluoroscopy to ensure that the blade follows the path made by the chisel.
Once the blade is seated, the most proximal screw is placed through the implant into the medial cortex of the proximal femoral neck, rigidly securing the implant to the proximal fragment.
Fracture reduction is now achieved by bringing the plate to the shaft and controlling length and rotation.
A femoral distractor may be used on the lateral aspect of the femur, with the proximal pin in the head and neck fragment and the distal pin placed distal to the end of the plate.
Distraction is applied across the fracture to gain fracture alignment and length through soft tissue tensioning using an indirect reduction technique.
A bone clamp is loosely applied to the distal femoral shaft fragment and plate to counteract the tendency for the fracture to be reduced into varus with the femoral distractor.
TECH FIG 4 • Blade plate insertion. A,B. Preoperative AP and lateral radiographs of a 31-A3 fracture in a 28-year-old man. C. Chisel inserted after femoral head and neck and trochanteric block were secured with lag screws. D. Insertion of blade plate. E. Postoperative AP radiograph.
Pointed reduction clamps are used to reduce comminuted fragments to the plate without stripping them of soft tissue attachments.
With the fracture alignment and length restored, it is checked with fluoroscopy.
If acceptable, the distraction is reduced to allow fragment settling and fracture compression.
The plate is then fixed to the shaft fragments with screws in the standard manner, and lag screws are inserted where the pointed reduction clamps were previously placed.
The final fracture alignment and length, as well as the femoral head, are examined with fluoroscopy to ensure proper fracture reduction and to make sure that there has been no head penetration by the implant.
WOUND CLOSURE
Aggressive débridement of devitalized tissue is performed before wound irrigation.
The wound is then closed in a layered fashion; the muscle, fascia, subcutaneous tissue, and skin are repaired separately.
POSTOPERATIVE CARE
Anteroposterior and lateral radiographs of the operative hip should be obtained immediately postoperatively in the recovery room to assess implant position and fracture reduction and to ensure that no iatrogenic femur fracture was produced intraoperatively. The entire device should be included in the radiograph (FIG 6).
Patients are mobilized as soon as their cardiopulmonary and mental status will safely allow, usually by postoperative day 1.
Unrestricted immediate postoperative weight bearing is easiest for the patient to comply with, and multiple investigations have shown no increase in fixation failure as a result of this postoperative rehabilitation protocol.7
FIG 6 • Postoperative AP and lateral radiographs showing correct implant positioning and no intraoperative complications.
Koval et al8 used gait analysis to show how patients effectively autoregulate their weight bearing postoperatively, with the patients who had the least-stable fracture patterns preoperatively putting the least amount of weight on their legs immediately postoperatively.
Patients should be seen 2 weeks postoperatively to check for uneventful wound healing.
Follow-up radiographs should be obtained at 2, 6, and 12 weeks to check for controlled fracture impaction, exclude any fixation device complications, and assess fracture healing.
OUTCOMES
With proper fracture reduction, implant selection, and fixation device positioning, peritrochanteric hip fractures heal in up to 98% of cases.
One-year mortality rates after fixation of peritrochanteric hip fractures range from 7% to 27%, with most studies finding a rate of 15% to 20%.10
Mortality rates depend on both preoperative and postoperative medical complications and condition, as well as preoperative functional status.
Postoperative functional status also depends on numerous variables:
Socioenvironmental functional status has been shown to be of great importance in determining the postoperative function status of a patient.10
FIG 7 • A. Varus collapse. B. OTA 31-A1 intertrochanteric hip fracture fixed with a sliding hip screw. C. Follow-up radiograph 6 months postoperatively showing secondary fracture displacement.
Longitudinal studies comparing the functional status of patients before and after hip fracture fixation have documented that roughly 40% of patients maintain their preoperative level of ambulation postoperatively.
Another 40% of patients have increased dependency on ambulation devices but remain ambulatory.
Twelve percent of patients become household-only ambulators, and 8% of patients become nonambulators postoperatively.5
COMPLICATIONS
Loss of proximal fixation is defined as varus collapse of the proximal fracture fragment with cutout of the lag screw from the femoral head (FIG 7A). This complication is seen in 4% to 20% of fractures, usually within 4 months of surgery.
Although certain fracture patterns have been shown to have a higher rate of proximal fixation loss, the fracture pattern cannot be controlled by the physician.
The placement of the lag screw, on the other hand, can be controlled by the physician. A central and deep position with a tip–apex distance of less than 25 mm has been shown to significantly reduce the incidence of proximal fixation loss.2
Nonunion occurs in 1% to 2% of fractures. The low incidence is likely due to the well-vascularized nature of the cancellous peritrochanteric region of the hip through which these fractures develop.
Secondary fracture displacemen.
Despite adequate fracture reduction and implant positioning, fractures may progress to excessive impaction, with resultant limb shortening and abductor weakening (FIG 7B,C). This can lead to suboptimal patient functional results. This is often seen in cases of unrecognized lateral wall fractures (either iatrogenically induced by implant placement or unrecognized from the original trauma).
Use of intramedullary fixation devices and vigilant follow-up may help avoid this complication.
Infection
Wound dehiscence
REFERENCES
1. Baumgaertner MR, Curtin SL, Lindskog DM, et al. The value of the tip-apex distance in predicting failure of fixation of peritrochanteric fractures of the hip. J Bone Joint Surg Am 1995;77A:1058–1064.
2. Baumgaertner MR, Solberg BD. Awareness of tip-apex distance reduces failure of fixation of trochanteric fractures of the hip. J Bone Joint Surg Br 1997;79B:969–971.
3. Bolhofner BR, Russo PR, Carmen B. Results of intertrochanteric femur fractures treated with a 135-degree sliding screw with a two-hole side plate. J Orthop Trauma 1999;13:5–8.
4. Griffen JB. The calcar femorale redefined. Clin Orthop Relat Res 1982;164:211–214.
5. Koval KJ, Friend KD, Aharonoff GB, et al. Weight bearing after hip fracture: a prospective series of 596 geriatric hip fracture patients. J Orthop Trauma 1996;10:526–530.
6. Koval KJ, Sala DA, Kummer FJ, et al. Postoperative weight-bearing after a fracture of the femoral neck or an intertrochanteric fracture. J Bone Joint Surg Am 1998;80A:352–356.
7. Koval KJ, Skovron ML, Aharonoff GB, et al. Ambulatory ability after hip fracture: a prospective study in geriatric patients. Clin Orthop Relat Res 1995;310:150–159.
8. Kregor PJ, Obremskey WT, Kreder HG, et al. Unstable pertrochanteric femoral fractures. J Orthop Trauma 2005;19:63–66.
9. McLoughlin S, Wheeler DL, Rider J, et al. Biomechanical evaluation of the dynamic hip screw with two- and four-hole sideplates. J Orthop Trauma 2000;14:318–323.
10. Miller CW. Survival and ambulation following hip fracture. J Bone Joint Surg Am 1978;60A:930.
11. Moran CG, Wenn RT, Sikand M, et al. Early mortality after hip fracture: is delay before surgery important? J Bone Joint Surg Am 2005;87:483–489.
12. Pajarinen J, Lindahl J, Michelsson O, et al. Peritrochanteric femoral fractures treated with a dynamic hip screw or a proximal femoral nail: a randomised study comparing postoperative rehabilitation. J Bone Joint Surg Br 2005;87:76–81.
13. Rao JP, Banzon MT, Weiss AB, et al. Treatment of unstable intertrochanteric fractures with anatomic reduction and compression hip screw fixation. Clin Orthop Relat Res 1983;175:65–71.
14. Ruby L, Mital MA, O'Connor J, et al. Anteversion of the femoral neck. J Bone Joint Surg Am 1979;61:46–51.
15. Utrilla AL, Reig JS, Munoz FM, et al. Trochanteric gamma nail and compression hip screw for trochanteric fractures: a randomized, prospective, comparative study in 210 elderly patients with a new design of the gamma nail. J Orthop Trauma 2005;19:229–233.
16. Winter WG. Nonoperative treatment of proximal femoral fractures in the demented, nonambulatory patient. Clin Orthop Relat Res 1987;218:97–103.
17. Zuckerman JD, Skovron ML, Koval KJ, et al. Postoperative complications and mortality associated with operative delay in older patients who have a fracture of the hip. J Bone Joint Surg Am 1995;77A:1551–1556.