Little has been written on randomized, controlled studies of operative
versus nonoperative management of Pipkin type-II fractures associated with
posterior dislocation of the hip. It is difficult to validate the optimal
management of these fractures. The goals of this study were to (1) evaluate the
results of conservative and surgical treatment for Pipkin type-II fractures
associated with posterior dislocation of the hip and supply the optimal
management for these fractures and (2) identify whether the Smith-Petersen
approach is a safe and reliable surgical approach for Pipkin type-II fractures.
Twenty-four patients were randomly divided into 2 groups: the
conservative group (n=12) was treated by closed reduction, and the surgical
group (n512) was treated by primary open reduction internal fixation (ORIF) by
bioabsorbable screws via a Smith-Petersen approach. Minimum follow-up was 24
months. Functional outcome was measured using the Thompson and Epstein score
and the d’Aubigné-Postel score. Heterotopic ossification was
classified based on the Brooker classification. The outcome of the conservative
group was worse than that of the surgical group (P=.037). Two patients
in the conservative group needed joint replacement for avascular necrosis of
the femoral head. Heterotopic ossification was found in 6 patients (1 patient
in the conservative group and 5 in the surgical group).
Primary ORIF by bioabsorbable screws via a Smith-Petersen approach is
an effective treatment for Pipkin type-II fractures associated with posterior
The Pipkin classification system is the most commonly used to evaluate
fractures (Figure 1). Pipkin type-II fracture of the femoral head associated
with posterior dislocation of the hip is an uncommon but severe
injury.1 Statistics show that 11.7% of hip dislocations were
associated with a femoral head fracture and that 84% of patients had been
victims of an automobile accident.2 The fracture itself, as well as
posttraumatic changes such as heterotopic ossification, avascular necrosis of
the femoral head, and osteoarthritis, may lead to a restriction in hip function
and permanent disability, even in young patients.
|Figure: Pipkin classification of femoral
head fractures with posterior hip dislocations.
The absence of a validated outcome instrument has contributed to the
lack of absolute recommendations and indications for the most appropriate
treatment of these injuries.3 Little has been written to date on
prospective, randomized, controlled studies of operative versus nonoperative
management of Pipkin type-II fractures, and no clear evidence exists that
indicates whether to treat the fracture operatively or nonoperatively.
For Pipkin type-II fractures, the main surgical approaches include
anterior (Smith-Peterson), posterior (Kocher-Langenbeck) and trochanteric-flip
osteotomy approaches. Advantages and disadvantages of the different approaches
have been the subject of previous studies, and controversies and
inconsistencies exist concerning the optimal surgical approach for these
The goals of this study were to (1) evaluate the results of
conservative and surgical treatment for Pipkin type-II fractures associated
with posterior dislocation of the hip by a randomized, controlled trial and
supply the optimal management for these fractures, and (2) identify whether the
Smith-Petersen approach is a safe and reliable surgical approach for Pipkin
Materials and Methods
We designed a randomized, controlled trial to compare the results of
conservative and surgical treatment for Pipkin type-II fractures associated
with posterior dislocation of the hip. Inclusion criteria were patients aged 18
to 60 years with close Pipkin type-II fractures of the femoral head associated
with posterior hip dislocation, time elapsed between injury and successful
closed reduction or ORIF <12 hours, and time to follow-up visit >2 years.
Exclusion criteria were associated posterior wall acetabular fracture, previous
hip injury, associated nerve or vascular injury, pathological fracture of the
femoral head, and associated severe multiple injuries, including brain
All patients were included based on written informed consent. This
study was approved by the Institutional Review Board and Ethics Committee of
In the conservative group, immediate closed reduction of a fracture
dislocation of the hip was performed under general or epidural anesthesia. The
limb was put into skeletal traction for 6 weeks after successful closed
reduction to restrict hip movement. Radiographs were taken immediately after
successful closed reduction, at 12 weeks postoperatively, and every 6 months
thereafter. Functional exercises of isometric contraction of the quadriceps
were started the day after closed reduction. When the radiographs at 12 weeks
showed fracture healing, progressive weight bearing and active exercises were
started. Full weight bearing was allowed 6 months after successful closed
reduction, but patients were instructed to avoid high-impact training.
In the surgical group, closed reduction was not attempted. After
admission, ORIF was performed immediately via the Smith-Petersen approach under
general or epidural anesthesia. With patients in the supine position, an
incision was started at the middle of the iliac crest and continued anteriorly
to the anterosuperior iliac spine and then distally and slightly laterally 10
to 12 cm, dividing the superficial and deep fasciae and freeing the attachments
of the gluteus medius and the tensor fasciae latae muscles from the iliac
crest. With a periosteal elevator, the periosteum, with the attachments of the
gluteus medius and minimus muscles, was stripped from the lateral surface of
the ilium, and bleeding from the nutrient vessels was controlled by packing the
interval between the ilium and the reflected muscles. Dissection was carried
through the deep fascia of the thigh and between the tensor fasciae latae
laterally and the sartorius and rectus femoris medially. The ascending branch
of the lateral femoral circumflex artery (5 cm distal to the hip joint) was
clamped and ligated.
The lateral femoral cutaneous nerve was passed over the sartorius 2.5
cm distal to the anterosuperior spine and retracted to the medial side. If the
structures at the anterosuperior spine were contracted, the spine was freed
with an osteotome and allowed to retract with its attached muscles to a more
distal level. The capsule was exposed and incised transversely and revealed the
femoral head and the proximal margin of the acetabulum. The capsule may also be
sectioned along its attachment to the acetabular labram (cotyloid ligament) to
give the required exposure. If necessary, the ligamentum teres may be divided
with a curved knife or with scissors and the femoral head dislocated, giving
access to all parts of the joint. The femoral head was dislocated to anterior
of the hip, and the head fragment was reduced and fixed with 2 to 3
bioabsorbable polylactate screws (2.5-3.0 mm). The intra-articular soft tissue
and small intra-articular bone fragments were cleaned up before hip reduction.
The limb was put in skin traction for 6 weeks postoperatively to restrict hip
movement. Other postoperative management was the same as that for the
conservative group. All surgical procedures were performed by the same surgeon
All patients were followed up by an independent person for at least 2
years. Patients were evaluated by radiographic outcomes, including rates of
avascular necrosis of the femoral head and heterotopic ossification, and
clinical outcomes using the Thompson and Epstein score13 and the
d’Aubigné-Postel score.14 Heterotopic ossification was
determined by the Brooker classification.15
Data were expressed as mean±standard deviation. Statistical
evaluation included separate unpaired t test, Pearson chi-square test,
and Wilcoxon rank-sum test. The Wilcoxon rank-sum test was used as a
nonparametric test to compare distributions in the 2 treatment groups. The
tests were performed using SPSS 12.0.1 for Windows (SPSS Inc, Chicago,
Illinois). A P value <.05 was considered statistically
From 2000 to 2008, 24 patients with Pipkin type-II fractures of the
femoral head were treated and divided randomly into 2 groups according to
sequence of admission. Each group comprised 12 patients. Patient data are
summarized in Tables 1 and 2.
In the conservative group, 9 men and 3 women had an average age at the
time of injury of 39.8±10.20 years (range, 26-59 years). Nine patients
sustained their injuries during a traffic accident, 2 fell from a height, and 1
was hit by a falling wall. The time elapsed from injury to successful closed
reduction was 5.2±2.40 hours (range, 1.5-10.0 hours). In the surgical
group, 8 men and 4 women had an average age at the time of injury of
37.5±12.14 years (range, 19-52 years). Ten patients sustained their
injuries during a traffic accident, and 2 fell from a height. The time elapsed
from injury to successful ORIF was 7.0±2.07 hours (range, 4.5-11.5
hours). Minimum follow-up was 26 months (mean, 39.1±8.79 months; range,
26-60 months) in the conservative group and 24 months (mean, 36.9±11.65
months; range, 24-65 months) in the surgical group. The 2 groups were
comparable (P>.05) with respect to age, sex, duration from injury to
reduction, and follow-up time (Table 3).
The femoral head fractures did not achieve anatomical reduction in the
conservative group (Figures 2-5), but achieved anatomical reduction in the
surgical group (Figures 6, 7). Outcomes by Thompson and Epstein score and
d’Aubigné-Postel score were classified equally. The treatment
results were divided into 4 grades: in the conservative group, the result was
excellent in 2 patients, good in 3, fair in 5, and poor in 2. In the surgical
group, the outcome was excellent in 5 patients, good in 5, fair in 2, and poor
in none. Wilcoxon rank-sum test analysis of these data reached statistical
significance (P=.037). The outcome was significantly better in the
surgical group than the conservative group (Table 4).
|Figure 2: Radiograph
of Pipkin type-II fracture associated with posterior dislocation of the hip.
Figure 3: CT scan of Pipkin type-II fracture associated with
posterior dislocation of the hip. Figure 4: Radiograph of
Pipkin type-II fracture after closed reduction.
|Figure 5: CT scan of
Pipkin type-II fracture after closed reduction. Figure 6:
Radiograph of Pipkin type-II fracture after ORIF. Figure 7: CT
scan of Pipkin type-II fracture after ORIF.
Avascular necrosis of the femoral head was not found in the surgical
group. In the conservative group, 2 patients required joint replacement for
avascular necrosis of the femoral head. Heterotopic ossification was found in 6
patients, 1 in the conservative group and 5 in the surgical group. Chi-square
analysis failed to reach statistical significance in the complication of
avascular necrosis (P=.140). The complication of heterotopic
ossification reached a near statistically significant difference
(P=.059) (Table 4).
Fractures of the femoral head have been well described in the
literature, but meaningful conclusions have proven difficult because of the
lack of high-quality randomized, controlled studies.2 Little has
been written to date on prospective, randomized, controlled studies of
operative versus nonoperative management of Pipkin type-II fractures, and there
is no clear evidence indicating whether to treat these fractures operatively or
nonoperatively. We therefore reported the radiographic outcomes, including
rates of avascular necrosis of the femoral head and heterotopic ossification,
and clinical outcomes using the Thompson and Epstein score and the
d’Aubigné-Postel score of 24 patients with Pipkin type-II fractures
managed conservatively or surgically with the Smith-Peterson approach during an
Our study has numerous limitations. First, the number of patients
enrolled in the trial was relatively small. A power analysis indicated that a
group of 10 patients would be sufficient to determine whether there was a
better outcome. We did not anticipate important differences in rates of
avascular necrosis of the femoral head and heterotopic ossification between the
groups, and although we found none, the group size would not be sufficient to
detect small differences in rates of avascular necrosis of the femoral head and
heterotopic ossification. Second, the assessor was also the caregiver and the
person who informed the patients about the goals of the study. Although the
intervention types did not allow blinding of patients, the study would have
been stronger by blinding the assessor for the functional outcome measurement
(clinical and radiographic hip score) or by using an independent assessor.
Third, this study had a comparative effectiveness design, and the lack of a
true control group may mean that the changes observed in both groups were not
real. Fourth, the follow-up visit was limited, with an average follow-up of
39.1±8.79 months in the conservative group and 36.9±11.65 months
in the surgical group. The study data should be viewed as preliminary and
requiring further development to substantiate conclusions regarding rate of
avascular necrosis of the femoral head.
The recommended treatment methods have varied from primary closed
reduction or ORIF for Pipkin type-II fractures of the femoral head associated
with posterior dislocation of the hip. Epstein et al5 suggested that
all traumatic dislocations of the hip must be treated as surgical emergencies,
that multiple attempts at closed reduction are contraindicated, and that the
good results after primary open reduction were better than closed or closed
followed by open reduction. Some studies suggest that conservative methods
should be considered initially, although treatment of this injury is
difficult.16,17 Others support immediate primary open reduction of
both dislocation and fractured fragments, because further trauma to the injured
soft tissues can be avoided and loose, harmful fragments can be simultaneously
debrided from the joint space.4,5,18,19 Prerequisites of such
treatment are anatomic reduction of hip dislocation and femoral head fracture,
but these are all difficult by closed reduction. A study by Henle et
al8 showed that only 1 in 12 patients showed an anatomic fracture
position after closed reduction; if the fracture gap within the joint showed a
displacement of >2 mm, operative treatment was indicated to improve
Nonoperative management cannot clean up the intra-articular soft
tissue and small bone fragments. We feel that the intra-articular soft tissue,
small intra-articular bone fragments, and malunion lead to osteoarthritis of
the hip and avascular necrosis of the femoral head. Our study shows that
primary ORIF for Pipkin type-II fractures associated with posterior hip
dislocation had a better outcome than primary closed reduction. Although the
complication of avascular necrosis of the femoral head failed to reach
statistical significance in our study, taking into account the small number of
patients, we presumed the complication was high in conservative management.
These results show that primary ORIF is an acceptable treatment of Pipkin
type-II fractures of the femoral head.
The matter of which operative approach should be used for the surgical
treatment of femoral head fractures remains controversial. Some studies
advocate the use of Kocher-Langenbeck approach and advise against the
Smith-Peterson approach, supposing that the latter would damage any residual
blood supply to the femoral head.4,5 Another study shows that when
evaluated with an odds ratio analysis, the use of Kocher-Langenbeck posterior
approach was associated with a 3.2-times-higher incidence of avascular necrosis
development when compared with the Smith-Petersen approach.3 Gautier
et al20 showed that the medial femoral circumflex artery, mainly its
deep branch, supplies the blood to the femoral head. Recently, a
trochanteric-flip osteotomy approach has been recommended for femoral head
fractures.7,8,21 However, this approach increases the risk of
nonunion of the greater trochanter. In the current study and other
studies,3,10,12 the recommendation for treatment of Pipkin type-II
fractures is the Smith-Petersen approach. There is a significant decrease in
operative time and estimated blood loss, and the approach improves
visualization and fixation with the anterior approach. The drawback in patients
treated with an anterior approach was the development of more functionally
significant heterotopic ossification, although the overall functional outcome
was identical in both groups.12 In our study, the outcome of the
surgical group was better than the conservative group, but the incidence of
heterotopic ossification in the surgical group was high. Prophylaxis with
indomethacin or low-dose radiation should be considered to minimize heterotopic
It was difficult to ensure a safe time interval between injury and
reduction of traumatic dislocation of the hip joint. McMurtry and
Quaile22 showed that the joint should be relocated within 6 hours;
failure to do so increases the risk of avascular necrosis of the femoral head
with resultant early degenerative joint disease, often in an otherwise fit,
young patient. Epstein et al5 indicated that reduction within 24
hours gives better results than late reduction. Our study shows that reduction
by surgical treatment for these fractures within 12 hours can give good
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- Giannoudis PV, Kontakis G, Christoforakis Z, Akula M, Tosounidis
T, Koutras C. Management, complications and clinical results of femoral head
fractures [published online ahead of print November 7, 2009]. Injury.
- Stannard JP, Harris HW, Volgas DA, Alonso JE. Functional outcome of
patients with femoral head fractures associated with hip dislocations. Clin
Orthop Relat Res. 2000; (377):44-56.
- Epstein HC. Traumatic dislocations of the hip. Clin Orthop Relat
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- Epstein HC, Wiss DA, Cozen L. Posterior fracture dislocation of the
hip with fractures of the femoral head. Clin Orthop Relat Res. 1985;
- Ganz R, Gill TJ, Gautier E, Ganz K, Krügel N, Berlemann U.
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- Marchetti ME, Steinberg GG, Coumas JM. Intermediate-term experience
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- Swiontkowski MF, Thorpe M, Seiler JG, Hansen ST. Operative
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- D’Aubigne RM, Postel M. Functional results of hip
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- Butler JE. Pipkin Type-II fractures of the femoral head. J Bone
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Drs Chen, Zhai, Ding, Lian, Kang, Guo, Liu, and Lin are from the
Department of Orthopedics, the 175th Hospital of PLA, Traumatic Orthopedics
Center of PLA, Southeast Hospital of Xiamen University, Zhangzhou Fujian
Province, PR China.
Drs Chen, Zhai, Ding, Lian, Kang, Guo, Liu, and Lin have no relevant
financial relationships to disclose.
Correspondence should be addressed to: Bin Lin, MD, the 175th Hospital
of PLA, Southeast Hospital of Xiamen University, Zhanghua Rd, Zhangzhou Fujian
Province, PR China, 363000 (email@example.com).