Extract
Brachial plexus birth palsy occurs in association with 0.1% to 0.4% of live
births. The majority of infants will demonstrate complete spontaneous
recovery, but some will have persistent neurologic deficits requiring surgical
intervention. Incomplete neurologic recovery leads to persistent limitations
of active shoulder abduction and external rotation, often accompanied by an
internal rotation contracture of the shoulder. In young patients, anterior
releases of the pectoralis major, subscapularis, and/or anterior shoulder
capsule combined with tendon transfers of the latissimus dorsi and teres major
to the rotator cuff may provide significant improvement in global shoulder
function. While effective in younger patients, latissimus dorsi and teres
major tendon transfers are not a viable option in older patients with severe
glenohumeral joint deformity. In these cases, external rotation osteotomies of
the humerus may provide improvements in global shoulder function.
Brachial Plexus Palsy
Brachial plexus birth palsy occurs in association with 0.1% to 0.4% of live
births. The majority of infants will demonstrate complete spontaneous
recovery, but some will have persistent neurologic deficits requiring surgical
intervention. Incomplete neurologic recovery leads to persistent limitations
of active shoulder abduction and external rotation, often accompanied by an
internal rotation contracture of the shoulder. In young patients, anterior
releases of the pectoralis major, subscapularis, and/or anterior shoulder
capsule combined with tendon transfers of the latissimus dorsi and teres major
to the rotator cuff may provide significant improvement in global shoulder
function. While effective in younger patients, latissimus dorsi and teres
major tendon transfers are not a viable option in older patients with severe
glenohumeral joint deformity. In these cases, external rotation osteotomies of
the humerus may provide improvements in global shoulder function.
Pearl et al.1
reported on a series of thirty-three children who were managed with
arthroscopic release of the shoulder either alone (nineteen children) or in
combination with a latissimus dorsi transfer (fourteen children). Four
of the nineteen patients who had an isolated release required a later
latissimus dorsi transfer because of recurrence of internal rotation
contracture. The fourteen children who had a latissimus dorsi transfer in
conjunction with the arthroscopic release were older, but none of them had
recurrence of the contracture. Eighteen of the thirty-three patients had a
pseudoglenoid deformity on magnetic resonance imaging, and the arthroscopic
release restored the humeral head to a centered position in the joint in all
eighteen.
Waters and Bae2
reported on their experience with humeral derotation osteotomy in forty-three
patients. The average rotational correction that was achieved during
derotational humeral osteotomy was 64°, with the greatest functional
improvement occurring in association with hand-to-mouth, hand-to-neck, and
external rotation activities.
Shoulder Instability
Robinson et al.3
performed a prospective cohort study of 252 patients ranging in age from
fifteen to thirty-five years who had persistent instability of the shoulder.
The patients were initially managed with sling immobilization and a physical
therapy program. The authors found that 55.7% of the patients had instability
within the first two years after the primary injury. The fifteen-year-old male
patients had the highest risk, with 86% having development of instability. In
contrast, the thirty-five-year-old female patients had only a 13% risk for the
development of instability. These data are useful for counseling adolescent
and young adult patients after a shoulder dislocation as well as for
developing treatment guidelines targeting higher-risk groups.
Slipped Capital Femoral Epiphysis
It is well documented that recognition of a slipped capital femoral
epiphysis can be difficult because some patients may only present with a limp
or knee pain. Loder et
al.4 looked at the
demographic factors (including gender, race, age, weight, height, and duration
of symptoms at the time of diagnosis) associated with slip severity in
patients with a stable slipped capital femoral epiphysis. They found that only
age and the duration of symptoms were associated with slip severity. The final
prediction model suggested that if the child is more than 12.5 years of age at
the time of diagnosis, there is a twofold increased risk of having a slip
angle in excess of 30°, and, if the duration of symptoms has been greater
than two months, the risk of a moderate to severe slip is increased fourfold.
In addition, Loder et
al.5 reaffirmed the
importance of age, height, and weight in distinguishing a typical idiopathic
slipped capital femoral epiphysis from an atypical slipped capital femoral
epiphysis due to conditions such as endocrinopathy, metabolic disorders, or
radiation therapy. The single most useful predictor of endocrinopathy in
patients with a slipped capital femoral epiphysis was found to be a height
under the tenth percentile for age, which had a sensitivity of 75%, a
specificity of 97%, a positive predictive value of 75%, and a negative
predictive value of 97%.
Legg-Calvé-Perthes Disease
Surgical containment in the early phase of Legg-Calvé-Perthes
disease can be accomplished with a femoral varus osteotomy or an innominate
osteotomy. Domzalski et
al.6 measured the
acetabular growth in hips that had undergone a labral support shelf procedure
and compared it with that in a group of hips that had undergone a femoral
varus osteotomy for the treatment of Legg-Calvé-Perthes disease. They
found that, instead of inhibiting acetabular depth growth, a carefully
performed shelf procedure that does not damage the lateral growth center can
stimulate the development of acetabular depth. Furthermore, this stimulatory
effect lasts approximately three years and is coincident with gradual
resorption of the shelf, thus providing containment that is self-limiting in
its duration. This procedure may be an alternative to femoral varus osteotomy
and innominate osteotomy as a primary containment method.
Developmental Acetabular Deformities: Protrusio, Dysplasia,
Retroversion
Various acetabular deformities such as acetabular dysplasia, retroversion,
and protrusio can cause joint damage because of the abnormal mechanics of the
hip joint. The clinical outcome following a pelvic osteotomy for the treatment
of hip dysplasia depends on the optimal placement of the acetabular fragment,
the technical execution of the surgery without major complications, and the
status of the acetabular cartilage. Cunningham et
al.7 utilized an
advanced magnetic resonance imaging technique that images the charge density
of articular cartilage. This technique is called delayed gadolinium-enhanced
magnetic resonance imaging of cartilage (dGEMRIC). This technique is able to
detect cartilage degeneration before the onset of radiographic changes. The
authors found that dGEMRIC assessment of cartilage degeneration is a useful
tool for identifying poor candidates for a joint-preserving pelvic osteotomy
for the treatment of hip dysplasia. Imaging techniques such as this one
improve our understanding of various developmental conditions that can lead to
osteoarthritis because plain radiographs are insensitive to early degenerative
changes and do not correlate with patient symptoms.
Acetabular protrusio can lead to limited range of hip motion and cartilage
damage due to impingement and is common in Marfan syndrome. However, the
natural history of joint degeneration and the prevalence of this deformity are
not well understood. Sponseller et
al.8, in a
cross-sectional analysis of 173 patients with Marfan syndrome, looked at the
prevalence of acetabular protrusio as well as the association between patient
symptoms and radiographic changes associated with osteoarthritis and
acetabular protrusio. The authors found that the prevalence of protrusio
increased to approximately 35.9% by the age of twenty years and then it
plateaued; however, its presence did not correlate with osteoarthritic changes
as measured with the Iowa hip score in patients more than forty years of age.
They found a significant positive correlation between protrusio and hip pain
and a significant negative correlation between joint space width and protrusio
in symptomatic hips, suggesting that mechanical factors from the protrusio are
a contributor to joint degeneration but may not be the dominant factor.
Acetabular retroversion occurs when there is anterior overcoverage of the
femoral head by the anterior aspect of the acetabulum, and it is thought to be
a cause of joint degeneration. Ezoe et al. looked at the prevalence of
acetabular retroversion on the radiographs of the hips of patients with
idiopathic osteoarthritis, developmental dysplasia, Legg-Calvé-Perthes
disease, and adult-onset osteonecrosis. They found that normal hips and hips
with adult-onset osteonecrosis had a 6% prevalence of acetabular retroversion.
In contrast, the prevalence of acetabular retroversion was 18% for hips with
developmental dysplasia and 42% for those with Legg-Calvé-Perthes
disease. This study demonstrated that acetabular retroversion is commonly seen
in patients with childhood developmental disorders. This is useful information
when reconstructing these hips in order to avoid the creation of secondary
impingement.
Congenital deficiency of the cruciate ligaments of the knee is rare, with a
prevalence of approximately two per 100,000 live births, but it is commonly
seen in association with congenital femoral deficiency and fibular hemimelia.
Manner et al.9
analyzed thirty-four knees in limbs with congenital femoral deficiency and/or
fibular hemimelia and found that 55% had hypoplasia or aplasia of the anterior
cruciate ligament with a normal posterior cruciate ligament (type-I
deficiency), 21% had aplasia of the anterior cruciate ligament and hypoplasia
of the posterior cruciate ligament (type-II deficiency), and 24% had total
absence of both cruciate ligaments (type-III deficiency). The radiographic
appearance of the tibial spines and the femoral notch were characteristic for
each type of dysplasia. In type-I deficiency, the lateral tibial spine was
hypoplastic or aplastic. In type-II deficiency, the lateral tibial spine was
aplastic and the medial spine was hypoplastic. In type-III deficiency, both
tibial spines were aplastic. Additionally, with progressive severity of the
dysplasia, there was progressive narrowing of the femoral notch. These plain
radiographic changes in the knee can be used to rapidly assess possible
ligamentous deficiencies in congenitally abnormal limbs.
Traumatic anterior cruciate ligament injuries are four to six times more
common in female athletes than in male athletes, and the majority occur in
association with noncontact activities during sudden deceleration when
running, changing direction, or landing from a jump. Pfeiffer et
al.10 designed a
prospective cohort study to look at the effectiveness of a plyometric-based
exercise program to reduce the incidence of noncontact anterior cruciate
ligament injuries in girls on 112 teams from fifteen high schools. The
treatment group participated in the Knee Ligament Injury Prevention (KLIP)
program, which is designed to improve jump-landing and running-deceleration
mechanics and was performed twice a week. The incidence of anterior cruciate
ligament injuries was 0.167 per 1000 exposures in the treatment group and
0.078 per 1000 exposures in the control group, suggesting no effect of this
exercise program in the prevention of anterior cruciate ligament injuries.
Clubfoot deformity occurs in association with approximately one to two per
1000 live births. The goals of both surgical and nonsurgical treatment are to
obtain initial correction of the foot deformity and then to maintain
correction and function over time. Dobbs et
al.11 performed a
minimum twenty-five-year follow-up study of clubfeet that were treated with a
soft-tissue surgical release. Forty-five patients with seventy-three clubfeet
were managed with either a posterior release and plantar fasciotomy or an
extensive combined posterior, medial, and lateral release. Thirty-nine of the
forty-five patients required additional surgical procedures by the time of the
latest follow-up, with most of those procedures being performed in adolescence
or early adulthood. The mean functional score on the Laaveg-Ponseti scale was
65.3, which was significantly lower than the score of 87.5 in a comparable
group of patients managed with the closed manipulation and casting method of
Ponseti. None of the patients in the surgically treated group had an excellent
result, and only one-third had a good result. There was significantly more
radiographic evidence of arthritis in the feet that were treated surgically,
and the amount of arthritis seen radiographically in the talonavicular joint
appeared to correlate significantly with foot disability.
Congenital vertical talus is an uncommon foot deformity that traditionally
has been treated with surgical release. Dobbs et
al.12 reported on
their initial experience with eleven patients who were managed with a less
invasive approach that appears to provide a good short-term outcome. With this
approach, the foot is manipulated and then is casted using the Ponseti
principles of weekly long-leg casting with gradual correction. The foot is
stretched into plantar flexion and inversion while counterpressure is applied
to the medial aspect of the head of the talus. In the study, a mean of five
casts was required for reduction of the navicular onto the head of the talus.
Most patients subsequently underwent percutaneous pinning of the talonavicular
joint and a percutaneous heel cord tenotomy. Three patients also had
fractional lengthening of the tibialis anterior or peroneal brevis tendon. The
percutaneous pin was retained for five weeks and then was removed in the
office. The foot was then placed into a solid ankle-foot orthosis in 15°
of dorsiflexion to maintain reduction of the talonavicular joint. Six feet in
three patients had a recurrent deformity as indicated by resubluxation of the
navicular on the head of the talus. None of the six feet with recurrence,
however, had pin fixation of the talonavicular joint. The authors concluded
that cast immobilization following serial manipulation together with
talonavicular pin fixation and tenotomy of the Achilles' tendon provides
outstanding results in patients with idiopathic congenital vertical talus.
Growth Prediction
Sanders et
al.13, in a study
of twenty-four skeletally immature girls, found that a Risser sign of 0 and an
open tricartilage acetabular cartilage correlated with peak height velocity.
They also noted that a radiograph of the hand is useful for determining
whether the digital phalangeal epiphyses are capped (post-peak height
velocity) or uncapped (pre-peak height velocity) because capping strongly
correlates with the timing of peak height velocity, an important parameter to
study when predicting curve progression. Dimeglio et al. identified the timing
of the ossification of the olecranon and correlated it with peak growth
velocity. These approaches have the advantage of allowing an easy and reliable
assessment of skeletal age in six-month intervals during the two years of peak
growth velocity.
Congenital Scoliosis
Guille et al. reviewed the type and prevalence of systemic and intraspinal
anomalies in a study of 266 patients with congenital deformities of the spine.
In their review, 15% of the patients had abnormal neurologic findings on
physical examination; overall, however, 44% of the patients had intraspinal
anomalies. The intraspinal anomalies were more common in patients with complex
patterns of vertebral involvement, congenital kyphosis, and kyphoscoliosis. In
addition, 56% of the patients overall had a renal abnormality as well. Bollini
et al.14 analyzed
twenty-one patients who had congenital scoliosis or kyphoscoliosis due to an
isolated lumbar hemivertebra. They described their surgical technique for the
removal of a single lumbar hemivertebra by means of a combined posterior and
anterior approach with the use of a short anterior and posterior convex-side
fusion. The average age of the patients at the time of surgery was 3.3 years,
and the authors reported excellent improvement, with 71.4% curve correction
(from 32.9° before surgery to 9.4° following surgery) at 8.6 years of
follow-up. The authors reported very few complications and concluded that it
is very safe to remove a single hemivertebra to restore normal spinal
alignment and that excellent long-term outcomes can be expected.
Scoliosis Bracing
Nachemson et al. analyzed curve progression at sixteen years of follow-up
in a study in which forty-one patients who had been managed with bracing were
compared with sixty-five patients who had been managed with observation only
for the treatment of adolescent idiopathic scoliosis. In the observation-only
group, the average curve at the time of follow-up was 35.9° and 50% of the
patients demonstrated a curve increase of >6° but only four patients
had a curve of >45°. In the bracing group, the average curve at the
time of follow-up was 31.8° and 48% of the patients had a curve increase
of >6° but only one patient had a curve of >45°. No patient in
either group had surgery after skeletal maturity. The authors concluded that
curves at the time of skeletal maturity progress slowly and that surgical
treatment probably is not necessary with or without brace treatment.
Danielsson et al.15
reviewed the long-term outcome with regard to spinal mobility and muscle
strength in a study of patients with adolescent idiopathic scoliosis who were
managed with either fusion (135 patients) or bracing (102 patients). The
authors found that lumbar spinal motion and muscle endurance were
significantly decreased following fusion and that, in the fusion group, the
length of the fusion correlated inversely with lumbar range of motion but the
finger-to-floor distance was not affected. The same group of authors analyzed
the outcome at ten years and demonstrated that patients had moderately reduced
health status and ability to perform activities of daily living after either
surgical treatment or brace treatment. Both groups had increased pain, with
the patients in the surgery group having less pain than those in the bracing
group.
Early-Onset Scoliosis and Thoracic Insufficiency
Akbarnia et al., in a review of twenty-one patients with early-onset
scoliosis who underwent fusion following treatment with the dual growing rod
technique, reported an improvement in the Cobb angle from 81°
preoperatively to 27.7° at the time of final fusion, with an increase in
the T1-to-S1 length from 24.4 cm preoperatively to 35.0 cm at the time of
final fusion. The authors concluded that maintenance of the primary curve
magnitude had been achieved, allowing for an improvement of the curve at the
time of final fusion. They also demonstrated that spinal growth occurs in
patients who are managed with this technique, especially when lengthenings are
performed more frequently. The same group of authors reported on their
experience with complications that had occurred in association with the dual
rod technique and specifically analyzed risk factors for their occurrence.
They reviewed forty-eight patients with early-onset scoliosis and reported
that younger patients and patients with longer treatment periods had higher
complication rates. The overall prevalence of complications was 60%, with a
major risk factor being the diagnosis of infantile idiopathic scoliosis. Wound
complications were more common when the lengthening interval was less than
seven months.
There has been recent interest in the evaluation of patients who have a
congenital spinal deformity together with chest wall abnormalities leading to
thoracic insufficiency syndrome. The vertical expandable prosthetic titanium
rib (VEPTR) has been effectively utilized for the treatment of these
challenging patients by expanding the chest during the growing years to allow
for maximum lung development while also treating the spinal deformity. The
VEPTR is placed onto the chest wall and/or spine to achieve this correction.
Mayer and Redding reported changes in pulmonary function after VEPTR insertion
but demonstrated no significant change in FVC (forced vital capacity), FEV1
(forced expiratory volume in the first second of a forced expiratory
maneuver), total lung capacity, or residual volume at the first postoperative
visit. They stated that age has no impact on the change in pulmonary function
and speculated that this lack of change in pulmonary function may indicate
that lung volume preservation is occurring and that long-term improvements may
occur. Similarly, Song et al. analyzed lung function in eleven children
undergoing expansion thoracoplasty and demonstrated that improvements were
seen in some, but not all, children. These improvements were not predicted by
improvements in the Cobb angle. Vitale et al. administered the Child Health
Questionnaire to the primary caretaker of patients with thoracic insufficiency
syndrome and demonstrated significant perturbations in the quality of life,
obtaining some of the lowest scores observed in the pediatric population.
These data serve as an important baseline for future studies on patients
undergoing expansion thoracoplasty. Flynn et al. reported two-year data on a
multicenter population of twenty-four children who had undergone expansion
thoracoplasty for the treatment of congenital spinal deformity. The authors
reported improvements in the Cobb angle and the thoracic height over the
treatment period. However, there were seven cases of device migration and
infection or skin problems. Skaggs et al. reported a 2.1% incidence of
neurologic injury during primary VEPTR device implantation, with a 1.4%
incidence during device exchange and/or lengthening, which justifies the use
of neurologic monitoring of both the upper and lower extremities in these
patients. Patients who have a history of neurologic events related to VEPTR
use are more prone to subsequent events.
Thoracic Pedicle Screws in Scoliosis
The use of pedicle screws in the thoracic spine continues to increase, and
investigations into their use for the treatment of spinal deformity are
ongoing. Vitale et al. reported achieving overall similar coronal plane
correction with use of thoracic pedicle screws as compared with hooks for the
treatment of adolescent idiopathic scoliosis. Reliable deformity correction
was achieved with both methods. Patients managed with thoracic pedicle screws
had a decrease in thoracic kyphosis postoperatively. Jaffe et al. demonstrated
superior curve correction in patients with adolescent idiopathic scoliosis who
were managed with thoracic pedicle screws, with 83% correction of the thoracic
curve in patients who were managed with thoracic pedicle screws as compared
with a 52% correction in patients who were managed with hooks. Watanabe et al.
compared the use of wires, hooks, and screws for the treatment of curves
measuring >100° and demonstrated that apical pedicle screw constructs
were able to achieve and maintain better correction without instrumentation
failure in comparison with the other techniques. Lehman et al. reviewed the
position of 1023 pedicle screws, with 9.8% of the screws demonstrating
significant medial or lateral pedicle wall violations. Kyphotic deformities
were associated with more frequent lateral wall violations than scoliotic
deformities were. However, no neurologic, vascular, or visceral complications
were seen. Rajasekaran et al. analyzed the accuracy of navigated and
non-navigated thoracic pedicle screws placed during spinal deformity surgery
and demonstrated reduced surgical time, reduced radiation exposure time,
decreased pedicle perforation, and enhanced accuracy in association with the
navigation surgery. Lehman et al. analyzed 103 consecutive patients with a
minimum duration of follow-up of three years whose curves had been treated
with a pedicle-only screw construct. The authors reported 68% correction of
the main thoracic curve, with excellent coronal and sagittal balance and
improved apical vertebral rotation being achieved at the time of follow-up.
There were no construct-related complications or decompensations,
pseudarthroses, or neurologic deficits in this group of patients. Shah et al.
described a learning curve for the placement of thoracic pedicle screws and
demonstrated an association between cumulative experience and performance
improvement and outcome in the experience of a single surgeon. They estimated
that consistent screw placement with excellent results generally will occur
after approximately thirty cases.
Neuromuscular Disorders
Parent et al. reviewed a very large series of seventy-eight patients with
spinal muscular atrophy who underwent surgical correction of a spinal
deformity. The authors reported an improvement in the major Cobb angle from
78.9° to 40.5° as well as an improvement in sagittal and pelvic
balance. Vital capacity was consistently maintained as well. There was a 41%
rate of complications, and the authors concluded that spinal deformity can be
effectively treated in patients with spinal muscular atrophy; however, it does
require a multidisciplinary team as well as careful preoperative and
postoperative management. Two studies analyzed the use of medications to
decrease intraoperative blood loss in patients with neuromuscular scoliosis.
Shapiro et al. analyzed the use of tranexamic acid, a synthetic
antifibrinolytic agent, in patients with Duchenne muscular dystrophy
undergoing posterior instrumentation and fusion for the treatment of
scoliosis. There was a significant decrease in blood loss in the group managed
with tranexamic acid (1976 mL) as compared with controls (3382 mL). Similarly,
Shah et al. analyzed the effect of aprotinin on intraoperative blood loss in
patients with neuromuscular scoliosis and demonstrated a decrease in blood
loss when it was used (1673 compared with 2877 mL). Watanabe et al. analyzed
overall satisfaction with deformity surgery in patients with cerebral palsy
and demonstrated a 92% satisfaction rate as reported by the patient or family.
Sitting balance was improved in 87% of the patients, cosmesis was improved in
94%, and quality of life was improved in 66%. Tolo et al. reviewed
seventy-nine patients with scoliosis and a Chiari type-I malformation and
syringomyelia who were managed with cranial-cervical decompression. Among the
forty-nine patients with a curve of <20°, none had progression of the
curve. Among the thirty patients with a larger curve, seven had a reduction in
curve size, seven had no change, nine required bracing, and seven required
operative correction of the scoliosis. The authors concluded that the
treatment of Chiari type-I malformations may decrease the need for bracing or
surgical treatment of the scoliosis.
Anterior Surgery
In the study by Lonner et
al.16,
thoracoscopic fusion and instrumentation was compared with posterior spinal
fusion and instrumentation for the treatment of thoracic adolescent idiopathic
scoliosis. The authors found that the overall coronal plane curve correction
and the thoracic kyphosis and coronal plane balance that were achieved were
the same in the two groups. The operative time was greater in the
thoracoscopic group; however, the number of fusion levels and the amount of
blood loss were less in the thoracoscopic group and the patients in that group
scored better on the final Scoliosis Research Society outcomes questionnaire.
Newton et al. demonstrated that, in the treatment of thoracic scoliosis,
thoracoscopic instrumentation had a less detrimental effect on pulmonary
function at two years than open thoracotomy did. Patients in the thoracoscopic
group also had recovery to their preoperative status (or better) in terms of
nearly all measures of pulmonary function at the time of follow-up, whereas
those in the open thoracotomy group remained below their preoperative baseline
status at that time. Sucato et al. compared anterior and posterior
instrumentation and fusion for the treatment of Lenke type-1A curves and
demonstrated that anterior spinal fusion preserves motion segments and results
in significantly better coronal plane correction with an improved position of
the lowest instrumented vertebra. However, anesthesia time was increased for
the anterior instrumentation group because several patients were managed with
a thoracoscopic approach.
Complications
Puno et al., in a prospective, multicenter study of 702 patients who
underwent surgical treatment of adolescent idiopathic scoliosis, reported an
overall prevalence of non-neurologic complications of 16%. Five patients
required a reoperation: two because of early infection and three because of
implant failure. Braun et
al.17, in a review
of 364 patients who had surgery for the treatment of spinal deformity, found
that seventeen patients (4.7%) had development of superior mesenteric artery
syndrome. Multivariate logistic regression analysis identified the predictive
factors for this complication to be a staged procedure, a Lenke lumbar
modifier of B or C, a low body mass index, and increased thoracic stiffness.
Sucato et al., using multivariate logistic regression analysis, identified
three risk factors for the development of a delayed infection following
posterior surgery for the treatment of adolescent idiopathic scoliosis: having
a positive medical history of significant illness, receiving a blood
transfusion, and not having a postoperative drain. Kuklo et al. evaluated
surgical revision rates in patients with adolescent idiopathic scoliosis and
concluded that all pedicle screw constructs are associated with a lower
surgical revision rate when compared with other approaches. Rathjen et al.
reported that twenty-two of twenty-nine patients had development of a kyphosis
of =11° following implant removal after posterior spinal fusion and
instrumentation for the treatment of adolescent idiopathic scoliosis. The
increase in kyphosis correlated with decreased outcome scores. Burton et al.,
in a review of their experience with 208 consecutive patients undergoing
surgical treatment of adolescent idiopathic scoliosis, demonstrated a 9.1%
reoperation rate, with most reoperations being performed because of
pseudarthrosis, delayed deep infection, implant prominence, or
spondylolisthesis. Eight patients had late operative site pain, which was
directly related to the use of threaded transverse rod connectors. Those
devices have been replaced by closed drop entry transverse connectors
today.
Spondylolisthesis
Furey et al. reviewed their experience with twenty-two pediatric patients
with high-grade spondylolisthesis who underwent a posterior decompression and
posterolateral fusion with a fibular dowel graft. The slip angle, sacral
inclination, slip grade, and pelvic incidence were not found to significantly
affect clinical outcome in these patients. Transient neuropraxia occurred in
four patients, without persistent neurologic deficits, and lumbar lordosis
improved by an average of 6°. Hresko et al. evaluated sagittal spinal
pelvic alignment in patients with high-grade spondylolisthesis and defined two
subgroups of patients: (1) those with a high pelvic incidence and a low sacral
slope and (2) those with a low pelvic incidence and a high sacral slope. The
authors concluded that treatment strategies for a high-grade spondylolisthesis
may differ for these two groups of patients.
Spinal Cord Monitoring
Auerbach et al. reviewed 488 consecutive pediatric patients who underwent
multimodal spinal cord monitoring, which included transcranial motor evoked
potentials and somatosensory evoked potentials during the surgical correction
of adolescent idiopathic scoliosis. They found that transcranial motor evoked
potentials were more sensitive than somatosensory evoked potentials for
identifying potential spinal cord injury and for monitoring recovery.
Furthermore, this method allows for time to respond and avoid any permanent
neurologic injury. The authors also reported that there were no false-negative
results with this method.
Forearm Fractures
Price et al. analyzed reimbursement for and practice variation in the
treatment of nondisplaced distal radial fractures and concluded that the
avoidance of return visits saves money for patients and also provides greater
reimbursement for physicians. The authors did caution that the study did not
address clinical outcomes associated with this relatively minor injury.
However, previous published reports by Price supported splint immobilization
of buckle fractures without return appointments. Luhmann et al., in a study of
102 forearm fractures in children, compared the efficacy and adverse effects
of two methods of analgesia: (1) a combination of ketamine and midazolam and
(2) a combination of nitrous oxide and a hematoma block. Overall, the patients
who had nitrous oxide and a hematoma block experienced lower increases in
intra-procedure distress, less pain during fracture reduction, shorter
recovery times, and fewer adverse effects.
Jung et al., in a study of thirty children, compared two surgical
techniques for the treatment of unstable distal bothbone forearm fractures:
conventional Kirschner-wire fixation through the fracture line (sixteen
patients) and Kirschnerwire fixation with use of the transulnar technique
(fourteen patients). There were no differences between the groups in terms of
healing time, operative time, duration of hospital stay, or complications. The
authors concluded that the transulnar Kirschner wire fixation technique is a
good alternative for the treatment of high-risk fractures because it avoids
possible physeal injury, does not pass through the fracture line, and can
provide satisfactory results.
Tibial Fractures
Gordon et al. analyzed complications associated with the use of titanium
elastic nails for the treatment of tibial fractures in fifty-nine children.
Five fractures were associated with delayed healing, and two of these five
fractures were associated with a nonunion that required a secondary procedure.
The authors concluded that this type of fixation is effective; however, the
complication rate was high (19%) and included delayed unions and nonunions,
which had not been previously reported. Mubarak et al., in a study of 135
proximal tibial fractures, described a comprehensive classification system
that separated the fractures into four groups according to the deforming
force: extension (44%), flexion/avulsion (22%), valgus (21%), or varus (13%).
To our knowledge, that study represents the largest reported series of
proximal tibial fractures. Specific patterns of fracture type and injury
mechanism emerged, with trends toward Salter-Harris type-3 and 4 fractures
occurring as patients got older.
Supracondylar Fractures
Skaggs et al., in a multicenter study, reported on the occurrence of
compartment syndrome resulting from the treatment of supracondylar fractures
with use of closed reduction and pin fixation and then posed the question of
whether delaying the treatment of supracondylar humeral fractures perhaps has
gone too far. They reported on ten patients who had a compartment syndrome,
all of whom had pulses at the time of presentation. Eight of the ten patients
had a delay in fracture reduction and fixation (average delay, twenty-four
hours), and two of the ten patients had a fasciotomy twenty-five hours after
operative reduction. Kocher et al. described sixty flexion-type supracondylar
fractures and demonstrated a marked increase in the need for open reduction
when compared with extension-type fractures (29% compared with 10%),
especially among patients with type-3 flexion injuries. Eastwood et al., in a
study on the treatment of nerve injuries associated with supracondylar humeral
fractures, analyzed thirty-seven neuropathies associated with thirty-two
fractures. Thirty-eight percent of the nerve injuries were noted at the time
of initial presentation, whereas 62% were identified following fracture
treatment. The authors reported that surgical intervention was required for
almost one-third of the neuropathies associated with supracondylar fractures,
and excellent outcomes were not achieved in all patients despite surgical
decompression, neurolysis, excision of neuromas, and nerve-grafting. Leitch et
al.18 reported on
nine supracondylar humeral fractures that were graded as Gartland type-4
fractures because of severe instability. The authors described their technique
for the treatment of these fractures with use of closed reduction and
percutaneous pin fixation and reported overall excellent results, with no
instances of nonunion, cubitus varus, malunion, additional surgery, or loss of
motion.
Femoral Fractures
Gordon et al., in a retrospective series of eighty-eight patients, reported
on the use of rigid intramedullary nail fixation for the treatment of
pediatric femoral fractures, with the nail being inserted through the lateral
aspect of the greater trochanter. The patients were followed for a period of
eighteen months. There were no intraoperative or immediate postoperative
complications, and no patient had evidence of osteonecrosis. All of the
fractures healed radiographically within eight weeks after surgery.
Stevens et al., in a prospective study of thirty-four consecutive patients
with sixty-five segmental deformities who underwent implantation of an
extraperiosteal 8-plate, reported that the guided growth associated with the
use of the 8-plate provided a safe and cost-effective means of dealing with a
variety of deformities in children. Sanders et al., in a study of thirty-seven
patients who underwent screw epiphysiodesis for the correction of limb-length
inequality and angular deformity, reported excellent angular correction
overall, with the final limb-length difference averaging 0.1 cm. Complications
were related directly to incorrect placement of screws or implant
irritation.
Scaduto et al., in a study of thirty-three limbs in thirty-one patients
with transtibial amputations who underwent stump capping with use of the
proximal part of the ipsilateral fibula, reported a 12% rate of failure
(defined as the need for revision secondary to osseous overgrowth). The
authors concluded that this method is associated with low morbidity and is an
ideal way to prevent tibial overgrowth in children following amputation
through the bone. Raney et al., in a review of 116 lower limb lengthening
procedures in eighty-eight consecutive patients, demonstrated that lengthening
was associated with an increased complication rate when patients who had a
congenital limb-length discrepancy were compared with those who had an
acquired deficiency, although the lengthening percentage in the patients who
had a congenital deficiency was significantly higher. Stans et al., in a
report on a series of 100 patients who were managed with excision of a partial
physeal arrest, demonstrated that the average physeal growth was 78% in the
femur, 88% in the proximal part of the tibia, and 93% in the distal part of
the tibia.
Finally, Gordon et
al.19 analyzed the
distal part of the femur in patients with infantile tibia vara and reported
that the femur either was normal or had a varus deformity, with a mean lateral
distal femoral angle of 97°. The mean median proximal tibial angle in
these patients was 72°. The authors concluded that although patients with
infantile tibia vara most commonly had normal alignment of the distal part of
the femur, a substantial component of genu varum in children with late-onset
disease may occur in the distal part of the femur and therefore this component
should be considered when planning surgical treatment.
Cerebral Palsy
Soo et al.20
reviewed their experience with 323 patients from their registry in order to
determine the incidence of and risk factors for hip displacement in children
with cerebral palsy. The hip displacement rate for the entire cohort was 35%
and showed a linear relationship with the level of overall motor function.
Chang et al. reviewed their experience with thirty-one children with
neuromuscular hip dysplasia who underwent forty-one proximal femoral head
resections. They reported a high rate of heterotopic ossification in patients
who were managed with external fixation. However, 78% of the patients and
families demonstrated improvement in terms of their responses to questions
related to quality of life and 84% had improvement in their level of
satisfaction. Szalay demonstrated that bone mineral density correlated with
the prevalence of fractures in quadriparetic patients, but it is important to
distinguish between patients who have a low body mass index and those who have
a high body mass index when analyzing this fracture risk. Spiro et al., in a
study of eighty-four children with spastic cerebral palsy who underwent a
single-event multilevel surgical procedure, reported that the patients had
improvement in motor function postoperatively and that the improvement was
maintained over a period of five years. The patients who demonstrated the
greatest change had had intermediate levels of motor function preoperatively.
Otsuko et al., as part of a multicenter prospective study, analyzed
fifty-seven patients who underwent multilevel surgery for the treatment of
sagittal imbalance and gait disturbance and found that walking scores and
quality of life scores improved. The global Pediatric Outcomes Data Collection
Instrument (PODCI) score also improved, but no differences in the pain and
happiness scores were seen. The authors concluded that their findings
validated the use of multilevel surgery to improve sagittal balance and gait
in patients with cerebral palsy. Michlitsch et
al.21 analyzed the
muscular contribution to varus foot deformities in a study of seventy-eight
patients with cerebral palsy. The authors reported a higher prevalence of
anterior tibialis dysfunction, both in isolation as well as in combination
with posterior tibialis dysfunction, as a contributor to varus deformity in
these patients than had been reported previously. Essentially one-third of the
patients exhibited dysfunction of the tibialis anterior, one-third exhibited
dysfunction of the tibialis posterior, and one-third exhibited dysfunction of
both muscles. Molenaers et
al.22, in a
retrospective review of 424 children with cerebral palsy, analyzed the effect
of gait analysis and the administration of botulinum toxin type-A on the
timing and frequency of orthopaedic surgery. The authors demonstrated that
there was a delay in surgical treatment in patients who had a combination of
gait analysis and botulinum toxin injections, thus decreasing the frequency of
surgical procedures.
Infection
Caird et al.23
prospectively collected data on every child at a single institution who
underwent hip aspiration because of suspicion of septic arthritis. The authors
reported that fever was the best predictor of septic arthritis, followed by an
elevated C-reactive protein level and an elevated erythrocyte sedimentation
rate, refusal to bear weight, and an elevated serum white blood-cell count. A
C-reactive protein level of >2.0 mg/dL was a strong independent risk factor
for assessing and diagnosing children with septic hip arthritis.
Bone Tumors
In the study by Leet et
al.24, twenty-seven
patients with polyostotic fibrous dysplasia were analyzed with use of the
parent-child Pediatric Outcomes Data Collection Instrument. The scores were
lowest for sports and happiness. There was disagreement between the
adolescents and the parents with regard to sports (with the adolescent scores
being higher than the parental scores) and pain (with the parental scores
being higher than the adolescent scores). The overall global scores correlated
well between the parents and the adolescents. The authors concluded that the
loss of a normal femoral neck-shaft angle and the disease burden in the lower
extremities appear to have the greatest effects on the outcome scores.
Futani et al.25,
in a multicenter study, reported the results of a questionnaire that was
administered to forty children who had had limb-salvage surgery for the
treatment of a primary malignant tumor of the distal part of the femur. For
those who survived, the final functional score was 74% in the endoprosthetic
reconstruction group and 68% in the biological reconstruction group. For the
nineteen patients who underwent limb-lengthening, the mean functional score
increased significantly, from 62% before surgery to 81% after lengthening. In
the endoprosthetic group the most frequent complications were deep infection
and aseptic loosening, whereas in the biological reconstruction group the most
common complications were implant breakage and nonunion. The authors concluded
that both types of reconstruction can provide good functional results in
skeletally mature children with malignant bone tumors of the distal aspect of
the femur, despite a high rate of revisions and limb-lengthening procedures.
In the study by Snyder et
al.26, eighteen
patients who presented with a fracture through a benign skeletal lesion were
compared with eighteen patients who had an increased risk for fracture
according to current radiographic criteria but had not had a fracture over a
two-year period. The authors demonstrated that the combination of bending and
torsional rigidity as measured with quantitative computed tomography was more
accurate for predicting pathologic fractures through a benign bone lesion in
children than standard radiographic criteria. They recommended this computed
tomography-based method as a way of providing objective criteria for planning
the treatment of benign lesions.
The editorial staff of The Journal reviewed a large number of
recently published research studies related to the musculoskeletal system that
received a Level of Evidence grade of I. Over 100 medical journals were
reviewed to identify these articles, which all have high-quality study design.
In addition to articles cited already in this Update, four additional level-I
articles were identified that were relevant to pediatric orthopaedics. A list
of those titles is appended to this review after the standard bibliography. We
have provided a brief commentary about each of the articles to help to guide
your further reading, in an evidence-based fashion, in this subspecialty
area.
Betz RR, Petrizzo AM, Kerner PJ, Falatyn SP, Clements DH, Huss GK.
Allograft versus no graft with a posterior multisegmented hook system for the
treatment of idiopathic scoliosis. Spine. 2006;31:121-7.
In this prospective, randomized study, ninety-one patients with adolescent
idiopathic scoliosis were managed with posterior spinal fusion and
instrumentation either with or without allograft augmentation. Seventy-six
patients were followed for more than two years and were included in the
analysis. The allograft group included thirty-seven patients, and the
noallograft group included thirty-nine patients. Only one patient, in the
allograft group, had a definite pseudarthrosis. Two patients in each group met
the radiographic criteria for a possible pseudarthrosis, but there was no
difference between the two groups with respect to this complication.
There has certainly been a movement toward the use of allograft in order to
achieve fusion in patients with adolescent idiopathic scoliosis when they
undergo posterior spinal fusion and instrumentation. The question is whether
the use of allograft is necessary. The authors designed a study to analyze
this question and concluded that there was no difference between the two
groups. However, the incidence of pseudarthrosis is somewhat challenging to
define and perhaps, with the stiffer implants that are utilized today, a
two-year follow-up is not adequate to fully assess healing. The authors also
looked at a smaller subset of patients for a period of five years, and no
patient in either group had a pseudarthrosis. This is promising work, and if
the results hold true over time then this is certainly an advance in the
management of these patients.
Bohm ER, Bubbar V, Yong Hing K, Dzus A. Above and below-the-elbow
plaster casts for distal forearm fractures in children. A randomized
controlled trial. J Bone Joint Surg Am. 2006;88:1-8.
In this blinded, randomized, controlled trial, 102 children were managed
with either an above-the-elbow cast (fifty-six children) or a below-the-elbow
cast (forty-six children) for the treatment of a forearm fracture. The authors
demonstrated no difference between the groups with respect to initial fracture
reduction, post-reduction angulation, reangulation during cast immobilization,
or angulation of the fracture at the time of cast removal. Although several
patients met the criteria for remanipulation of the fracture, only four
patients actually underwent remanipulation. Those who were at most risk for
remanipulation were those who had fractures of both the radius and the ulna as
well as those with residual angulation after reduction. The authors noted that
the complication rates did not differ between the two groups, and they
concluded that either a below-the-elbow cast or an above-the elbow cast can be
utilized for most of these fractures.
Webb GR, Galpin RD, Armstrong DG. Comparison of short and long arm
plaster casts for displaced fractures in the distal third of the forearm in
children. J Bone Joint Surg Am. 2006;88:9-17.
In this prospective study, 113 patients with a displaced fracture of the
distal part of the forearm were randomized to treatment with either a short
arm plaster cast (fifty-three) or a long arm plaster cast (sixty). There were
no differences between the two groups with respect to preoperative factors,
including demographic or fracture characteristics. There was no difference
between the groups with regard to the change between the post-reduction and
final radiographs. However, the patients who were managed with a short arm
plaster cast were more independent with activities of daily living and missed
fewer school days. The authors concluded that, for patients who are older than
four years of age and who have a displaced fracture of the distal one-third of
the forearm, short arm casts are as effective as long arm casts.
This study and the study by Bohm et al. (discussed above) illustrate, in a
well-defined patient population, that a well-molded plaster short arm cast is
as effective as a long arm cast for maintaining good fracture reduction. The
advantage of the short arm cast as shown in the study by Webb et al. is that
patients are more independent with activities of daily living and do not need
to miss as many school days because a revisit to the physician is not
necessary to convert a long arm cast to a short arm cast. One of the things
that was not studied and may be a further advantage is that parents most
likely miss fewer work days and travel less to visit the physician when a
short arm cast is utilized. These studies provide excellent evidence that a
short arm cast is very effective for these patients, will decrease the need
for multiple physician visits, and will allow children to maintain a more
normal lifestyle than is the case when a long arm cast is utilized.
Zeifang F, Carstens C, Schneider S, Thomsen M. Continuous passive
motion versus immobilisation in a cast after surgical treatment of idiopathic
club foot in infants: a prospective, blinded, randomised, clinical study.
J Bone Joint Surg Br. 2005;87:1663-5.
Patients who had had surgical treatment of a clubfoot deformity were
randomized to either continuous passive motion (nineteen feet) or standard
cast immobilization (eighteen feet). The patients were then blindly evaluated
at six, twelve, eighteen, and forty months after surgery and were assigned a
Dimeglio clubfoot score as the prime outcome measurement. The authors
demonstrated that, at the time of early follow-up, the patients in the
continuous passive motion group had improved Dimeglio clubfoot scores.
However, after eighteen and forty-eight months, there were no differences
between the two groups.
One of the challenges following the surgical treatment of clubfoot is the
stiffness, which can lead to pain in the long term. Although it may seem
intuitive that continuous passive motion reduces stiffness following surgical
treatment, the results of this study suggest that continuous passive motion
does not have any intermediate-term benefit following surgical treatment.
However, the outcome measures that were used in this study (Dimeglio scores)
may not be ideal to fully assess flexibility and function. Given the results
of the study, however, postoperative casting is certainly acceptable and
appears to be an equally successful method when compared with continuous
passive motion.
Pearl ML, Edgerton BW, Kazimiroff PA,
Burchette RJ, Wong K. Arthroscopic release and latissimus dorsi transfer for
shoulder internal rotation contractures and glenohumeral deformity secondary
to brachial plexus birth palsy. J Bone Joint Surg Am.
2006;88:
564-74.88564
2006
[PubMed][CrossRef]
Waters PM, Bae DS. The effect of
derotational humeral osteotomy on global shoulder function in brachial plexus
birth palsy. J Bone Joint Surg Am.
2006;88:
1035-42.881035
2006
[PubMed][CrossRef]
Robinson CM, Howes J, Murdoch H, Will E,
Graham C. Functional outcome and risk of recurrent instability after primary
traumatic anterior shoulder dislocation in young patients. J Bone Joint
Surg Am. 2006;88:
2326-36.882326
2006
[CrossRef]
Loder RT, Starnes T, Dikos G, Aronsson
DD. Demographic predictors of severity of stable slipped capital femoral
epiphyses. J Bone Joint Surg Am.
2006;88:
97-105.8897
2006
[PubMed][CrossRef]
Loder RT, Starnes T, Dikos G. Atypical
and typical (idiopathic) slipped capital femoral epiphysis. Reconfirmation of
the age-weight test and description of the height and age-height tests.
J Bone Joint Surg Am.
2006;88:
1574-81.881574
2006
[PubMed][CrossRef]
Domzalski ME, Glutting J, Bowen JR,
Littleton AG. Lateral acetabular growth stimulation following a labral support
procedure in Legg-Calve-Perthes disease. J Bone Joint Surg Am.
2006;88:
1458-66.881458
2006
[PubMed][CrossRef]
Cunningham T, Jessel R, Zurakowski D,
Millis MB, Kim YJ. Delayed gadolinium-enhanced magnetic resonance imaging of
cartilage to predict early failure of Bernese periacetabular osteotomy for hip
dysplasia. J Bone Joint Surg Am.
2206;88:
1540-8.881540
2206
[CrossRef]
Sponseller PD, Jones KB, Ahn NU, Erkula
G, Foran JR, Dietz HC 3rd. Protrusio acetabuli in Marfan syndrome: age-related
prevalence and associated hip function. J Bone Joint Surg Am.
2006;88:
486-95.88486
2006
[PubMed][CrossRef]
Manner HM, Radler C, Ganger R, Grill F.
Dysplasia of the cruciate ligaments: radiographic assessment and
classification. J Bone Joint Surg Am.
2006;88:
130-7.88130
2006
[PubMed][CrossRef]
Pfeiffer RP, Shea KG, Roberts D,
Grandstrand S, Bond L. Lack of effect of a knee ligament injury prevention
program on the incidence of noncontact anterior cruciate ligament injury.
J Bone Joint Surg Am.
2006;88:
1769-74.881769
2006
[PubMed][CrossRef]
Dobbs MB, Nunley R, Schoenecker PL.
Long-term follow-up of patients with clubfeet treated with extensive
soft-tissue release. J Bone Joint Surg Am.
2006;88:
986-96.88986
2006
[PubMed][CrossRef]
Dobbs MB, Purcell DB, Nunley R,
Morcuende JA. Early results of a new method of treatment for idiopathic
congenital vertical talus. J Bone Joint Surg Am.
2006;88:
1192-200.881192
2006
[PubMed][CrossRef]
Sanders JO, Browne RH, Cooney TE,
Finegold DN, McConnell SJ, Margraf SA. Correlates of the peak height velocity
in girls with idiopathic scoliosis. Spine.
2006;31:
2289-95.312289
2006
[PubMed][CrossRef]
Bollini G, Docquier PL, Viehweger E,
Launay F, Jouve JL. Lumbar hemivertebra resection. J Bone Joint Surg
Am. 2006;88:
1043-52.881043
2006
[CrossRef]
Danielsson AJ, Romberg K, Nachemson AL.
Spinal range of motion, muscle endurance, and back pain and function at least
20 years after fusion or brace treatment for adolescent idiopathic scoliosis:
a case-control study. Spine.
2006;31:
275-83.31275
2006
[PubMed][CrossRef]
Lonner BS, Kondrachov D, Siddiqi F,
Hayes V, Scharf C. Thoracoscopic spinal fusion compared with posterior spinal
fusion for the treatment of thoracic adolescent idiopathic scoliosis. J
Bone Joint Surg Am. 2006;88:
1022-34.881022
2006
[CrossRef]
Braun SV, Hedden DM, Howard AW. Superior
mesenteric artery syndrome following spinal deformity correction. J
Bone Joint Surg Am. 2006;88:
2252-7.882252
2006
[CrossRef]
Leitch KK, Kay RM, Femino JD, Tolo VT,
Storer SK, Skaggs DL. Treatment of multidirectionally unstable supracondylar
humeral fractures in children. A modified Gartland type-IV fracture. J
Bone Joint Surg Am. 2006;88:
980-5.88980
2006
[CrossRef]
Gordon JE, King DJ, Luhmann SJ, Dobbs
MB, Schoenecker PL. Femoral deformity in tibia vara. J Bone Joint Surg
Am. 2006;88:
380-6.88380
2006
[CrossRef]
Soo B, Howard JJ, Boyd RN, Reid SM,
Lanigan A, Wolfe R, Reddihough D, Graham HK. Hip displacement in cerebral
palsy. J Bone Joint Surg Am.
2006;88:
121-9.88121
2006
[PubMed][CrossRef]
Michlitsch MG, Rethlefsen SA, Kay RM.
The contributions of anterior and posterior tibialis dysfunction to varus foot
deformity in patients with cerebral palsy. J Bone Joint Surg
Am. 2006;88:
1764-8.881764
2006
[CrossRef]
Molenaers G, Desloovere K, Fabry G, De
Cock P. The effects of quantitative gait assessment and botulinum toxin a on
musculoskeletal surgery in children with cerebral palsy. J Bone Joint
Surg Am. 2006;88:
161-70.88161
2006
[CrossRef]
Caird MS, Flynn JM, Leung YL, Millman
JE, D'Italia JG, Dormans JP. Factors distinguishing septic arthritis from
transient synovitis of the hip in children. A prospective study. J Bone
Joint Surg Am. 2006;88:
1251-7.881251
2006
[CrossRef]
Leet AI, Wientroub S, Kushner H,
Brillante B, Kelly MH, Robey PG, Collins MT. The correlation of specific
orthopaedic features of polyostotic fibrous dysplasia with functional outcome
scores in children. J Bone Joint Surg Am.
2006;88:
818-23.88818
2006
[PubMed][CrossRef]
Futani H, Minamizaki T, Nishimoto Y, Abe
S, Yabe H, Ueda T. Long-term follow-up after limb salvage in skeletally
immature children with a primary malignant tumor of the distal end of the
femur. J Bone Joint Surg Am.
2006;88:
595-603.88595
2006
[PubMed][CrossRef]
Snyder BD, Hauser-Kara DA, Hipp JA,
Zurakowski D, Hecht AC, Gebhardt MC. Predicting fracture through benign
skeletal lesions with quantitative computed tomography. J Bone Joint
Surg Am. 2006;88:
55-70.8855
2006
[CrossRef]