Clinical Trial Details
— Status: Active, not recruiting
Administrative data
| NCT number |
NCT02880501 |
| Other study ID # |
ChaohuH_001 |
| Secondary ID |
|
| Status |
Active, not recruiting |
| Phase |
N/A
|
| First received |
August 18, 2016 |
| Last updated |
August 23, 2016 |
| Start date |
January 2015 |
| Est. completion date |
December 2016 |
Study information
| Verified date |
August 2016 |
| Source |
Chaohu Hospital of Anhui Medical University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
China: Ministry of Health |
| Study type |
Interventional
|
Clinical Trial Summary
Minimally invasive PFNA fixation for the treatment of intertrochanteric femoral fracture
will be used in 20 patients within 2 years to objectively validate the safety and
effectiveness of PFNA in the treatment of fracture of long tube-like bone.
Description:
History and current status of related studies Intertrochanteric femoral fracture frequently
occurs in the elderly that is often complicated by different levels of osteoporosis, and
mostly belongs to unstable fractures. This disorder is also frequently complicated by
various chronic diseases, which make patients have poorer surgical tolerance. Surgical
treatment is the widely accepted treatment method of intertrochanteric femoral fracture
because it can accelerate the recovery and reduce the complications caused by long-term bed
time. Intertrochanteric femoral fracture is unstable and occurs mostly in the elderly, so
surgical treatment should meet the requirements including less risk of wound infection, less
intraoperative blood loss, great holding potential and strong stability of the implants,
which contribute to early hip joint function exercise and facilitate recovery after surgery.
According to the design principle of orthopedic implants, intramedullary and extramedullary
fixations are commonly used. Compared to extramedullary fixation, intramedullary fixation
places fixators closer to the affected region, produces shorter moment arm of force, better
shares the compression forces on the medial cortex of the femoral neck, exhibits higher
shear resistance, and provides greater stabilization for complex fractures in the elderly.
Compared to Garmma nail, an AO (Association for Osteosynthesis) proximal femoral nail has an
antirotation screw in the proximal end which ensures an elastic fixation of the fracture and
reduces the complications such as femoral shaft fractures. Nevertheless, 2 screws should be
installed in the femoral neck, which restricts the slippage between the main screw and the
compression screw, thus partial loading will be delivered through antirotation screws,
leading to occurrence of complications such as antirotation screw cutting and compression
screw withdrawal.
Conventional internal fixation methods including implantations of dynamic hip screws, Gamma
nails, and proximal femoral intramedullary nail exhibit unfavorable effects in the treatment
of intertrochanteric femoral fracture, in particular those complicated by severe
osteoporosis because these methods cannot achieve firm and reliable fixation with occasional
nail head cutting and nail withdrawal. Therefore, AO/ASIF (Association for
Osteosynthesis/Association for the Study of Internal Fixation) designed a novel antirotation
intramedullary nail, which better reduces the abovementioned complications.
Proximal femoral nail antirotation (PFNA) is a device designed based on proximal femoral
intramedullary nail and other intramedullary nails. This device is equipped with a spiral
wide blade which exhibits obvious antirotation and angular shear stress abilities, greatly
reducing complications and decreasing the possibility of surgical delay. Compared to
conventional screw systems, PFNA provides stronger antirotation and anti-inversion
abilities. For tapping of a spiral blade in the femoral neck, only lateral femoral cortex
should be opened without a need to remove bone matrix. The spiral blade tapped in the
femoral neck will produce compression to the bone in the femoral neck. Even though for
patients with severe osteoporosis, the spiral blade in the femoral neck can produce firm
anchoring force with the femoral neck. Compared with screw fixation, a spiral blade exhibits
a larger rotational torque, requires a smaller strength to be pulled out, and does not need
additional screws tapped in the femoral neck, so the latter is easier to be operated. The
PFNA has a medial-lateral angle of 6°, this allows insertion at the tip of the greater
trochanter. The distal diameter of the PFNA is relatively small, and its eccentricity is
reduced compared to that of intramedullary nails, which is more suitable to the anatomical
morphology of proximal femoral medullary cavity. The locking pores of the PFNA at its distal
tip include round static and oval-shaped dynamic types. Vertical installation of screws is
considered dynamic interlocking and oblique installation of screws static interlocking. From
the perspective of design, PFNA exhibits better biomechanical stability and shows advantages
in duration of surgery, intraoperative blood loss, failure rate of surgery and overall
complications over than internal fixation methods.
PFNA for the treatment of intertrochanteric femoral fracture in many cases has been
reported, but related studies are mainly retrospective case series, and a few retrospective
randomized controlled trials are reported.
Features different from other related studies Progress: PFNA is a device designed based on
modification of Garmma nail and it integrates the advantages of a dynamic hip screw (DHS)
used for extramedullary fixation and an intramedullary fixation device. PFNA exhibits more
advantages over DHS, including (1) smaller stress shielding, being more conducive to
fracture healing, and reduced cut-out phenomenon; (2) better shares the compressive stress
of medial femur, leading to lower incidence of hip deformity. Both proximal femoral
intramedullary nail and PFNA belong to intramedullary nails, but the latter exhibits the
following advantages: (1) one assembly can achieve antirotation and angular stability; (2)
the wide blade at the tip can compress as much peripheral matrix as possible, in particular
under the circumstance of osteoporosis, exhibiting better holding potential; (3) the blade
of PFNA is more closely attached to the matrix, which strengthens the stabilization of
implant and prevents against rotation and varus deformity; (4) biomechanical tests have
confirmed that the spiral blade can greatly increase shearing capacity; (5) spiral blades
are implanted via a lateral incision and internal fixation has the features including
minimal wound, less bleeding, satisfied reduction, rapid recovery, highly stable fractured
stumps, being more conducive to early exercise, avoidance of prolonged force arm caused by
extramedullary fixation, increased shear stress in the proximal femur, which greatly reduce
the possibility of failure of internal fixation.
Feasibility: Intramedullary nail for the treatment of long bone fracture has been widely
used in the clinic and expert consensus has been achieved. The novel PFNA for the treatment
of interchochanteric femoral fracture in the elderly produces minimal wound, is easily
performed, and is therefore highly feasible in the clinic. Our team has been ready for
performing this project from various perspectives: (1) Personnel: This project will be
equipped with 2 chief physicians, 2 associate chief physicians, 3 attending physicians, 2
resident physicians, and 1 graduate student. Our team has a strong clinical and scientific
research capacity. (2) Techniques: our team has performed open or closed reduction and
intramedullary nail fixation in many patients, so we are experienced, can provide
sophisticated surgical skills in orthopedic trauma and joint surgery. (3) Equipment: The
study setting has been equipped with orthopedic traction bed, X-ray, CT, MR scanners and
other large equipments. All of these can provide hardware and software support.
Safety: Under fluoroscopic guidance, closed reduction will be followed by minimally invasive
intramedullary nail fixation, which can effectively avoid vessel and nerve injury.
Data collection, management, analysis and open access Data collection: According to trial
design type and requirement, a table will be developed to record trial data. The recorded
data will be input into an electronic database using a double-data entry strategy by trained
professional staff.
Data management: Information accuracy will be checked when all recruited patients are
followed up. The database will be locked by the research in charge and will not be altered.
All information relating to this trial will be preserved by Chaohu Hospital of Anhui Medical
University, China.
Data analysis: The electronic database will be fully disclosed to a professional
statistician for statistical analysis.
Data open access: Anonymized trial data will be published at www.figshare.com.
Statistical analysis Statistical analysis will be performed using SPSS19.0 software. The
normally distributed continuous variables will be expressed as the mean ± standard
deviation, and those non-normally distributed variables will be expressed as median and
quartile. The categorical variables will be expressed as counts and the percentage. Paired t
test or Wilcoxon test (paired samples) will be used for comparison of continuous variables
between prior to and after PFNA implantation and the chi-square test for comparison of
categorical variables between prior to and after PFNA implantation. A level of P < 0.05 will
be considered statistically significant.
