James W. Roach

Immediate complications of Cotrel-Dubousset instrumentation to the sacro-pelvis. A clinical and biomechanical study.

The authors reviewed the early complications in all patients fused to the sacro-pelvis using Cotrel-Dubousset instrumentation at the Texas Scottish Rite Hospital. Sixteen patients were studied with an average follow-up of 13 months. Three methods of sacro-pelvis fixation were evaluated: iliosacral screws, sacral screws, and a technique whereby the caudle ends of the Cotrel-Dubousset rods were fashioned and inserted into the posterior iliac crest using the Galveston technique. Seven of the 16 sets of sacral screws (44%) failed during and after surgery. Two of the 7 sets of iliosacral screws failed postoperatively (28%). No failures occurred in the 8 sets of Cotrel-Dubousset rods placed with the Galveston technique. Seven of the nine medical complications observed (77%) occurred in the sacral screw group. Using calf spines, a biomechanical evaluation of each system was undertaken to determine strength of fixation. Each system was failed in flexion 3 times. The sacral screws were the weakest, pulling directly out of the sacrum at 40 N-M. Cotrel-Dubousset rods inserted with the Galveston technique were the strongest, experiencing rod deformities before flexion failure at 70 N-M. Iliosacral screws were of intermediate strength failing by rotation on the axis of the screws or pulling directly out of the ilium at 55 N-M. The authors conclude that using Cotrel-Dubousset rods inserted with the Galveston techniques was the strongest and safest method of sacro-pelvis fixation of the three tested

Familial predisposition to developmental dysplasia of the hip.

Background Developmental dysplasia of the hip (DDH) is a common birth defect and is thought to have genetic contributions to the phenotype. It is likely that DDH is genetically heterogeneous with environmental modifiers. The Utah Population Database (UPDB) is a computerized integration of pedigrees, vital statistics, and medical records representing over 6 million individuals, and is a unique resource providing the ability to search for familial factors beyond the nuclear family, decreasing the effect of a shared environment. The purpose of this study is to assess the degree of relationship between individuals with DDH. Methods Datasets were created from UPDB statewide birth certificates and from the University of Utah Health Sciences Center enterprise data warehouse using records for DDH and linked to the UPDB. Controls for the dataset were selected that matched cases on birth year and sex and 10 controls were selected per case. Statistics computed for each family were the number of descendants, the observed number of affected, the expected number of affected, P value, familial standardize incidence ratio, relative risks (RRs), and standard error. A kinship analysis tool was used to find pedigrees with excess DDH. Results The combined data resulted in 1649 distinct individuals with DDH. RR was significantly increased in first-degree relatives (RR=12.1; P<0.000001), siblings (RR=11.9; P<0.000001) and first cousins (RR=1.7; P=0.04). A total of 468 families were identified with at least 5 affected individuals in a family. These results were then filtered to only contain families that had a P value of less than 0.01. This resulted in 141 founders with anywhere between 4 and 30 affected living descendants with a P value of less than 0.01 with family sizes ranging from 594 to 44,819 descendants. A total of 28 founders had a familial standardize incidence ratio of greater than 5.0. Conclusions These data suggest a genetic contribution to DDH with a 12-fold increase in risk for first-degree relatives. Better phenotypic characterization and classification will be critical for future genetic analyses. Level of Evidence Prognostic level II.

Three-dimensional computer analysis of complex acetabular insufficiency.

Fourteen patients with acetabular dysplasia were studied by using three-dimensional computed tomography (CT) reconstructions before pelvic osteotomies. Computer manipulation of the data allowed a preoperative visual assessment of acetabular shape, assessment of potential congruency between the femoral head and acetabulum by using a mathematical best-fit sphere, and measurement of surface contact distances that depict joint coverage and relate to concentration of weight-bearing forces. Preoperative evaluation of the three-dimensional images for these 14 patients allowed improved understanding of their abnormal anatomy and better surgical planning.

Surgical correction of myelomeningocele scoliosis: a critical appraisal of various spinal instrumentation systems.

A retrospective review of 38 patients with myelomeningocele scoliosis, focusing on the incidence of eventual fusion, curve correction, and change in pelvic obliquity, was performed. Single stage anterior or posterior fusion was compared to combined anterior and posterior spinal fusion. Single stage anterior or posterior procedures resulted in only a 50% fusion rate compared to rates of 83 to 100% for various combinations of combined anterior and posterior fusions. Similarly, average curve correction and change in pelvic obliquity were much improved with a two-stage approach. No statistical difference in fusion rate, curve correction, or change in pelvic obliquity was noted between the various combinations of two-stage anterior and posterior fusions.

Corrective osteotomy for cubitus varus deformity

Between 1970 and 1992, 23 patients with cubitus varus deformities following elbow fractures underwent 26 corrective lateral-wedge osteotomies at Texas Scottish Rite Hospital. Internal fixation was most commonly provided by either small Steinmann pins, two screws and a figure-of-eight wire, or a small two-hole plate. Sixteen patients had a good result and 10 were judged to have poor results. Two of the 10 patients with poor results had inadequate intraoperative correction. Unstable internal fixation allowed osteotomy fragments to slip into varus in the remaining eight poor results (three with Steinmann pins and five with figure-of-eight wire). Nonrigid internal fixation was obvious even in the patients who received good correction of their cubitus varus. Of the 16 patients with good postoperative results, six demonstrated loss of fixation with extension of the distal fragment. In addition, seven patients with poor results also had slippage of the distal osteotomy fragment into extension. These patients had between 5 and 15 degrees of apparent elbow hyperextension with concomitant loss of elbow fixation. We now recommend a two-hole lateral plate and a percutaneous medial pin to enhance the stability of internal fixation.

Acetabular coverage: three-dimensional anatomy and radiographic evaluation.

Summary: The three-dimensional relationship between acetabulum and femoral head, known as coverage, was evaluated radiographically using a modified inlet view of the pelvis. The relationship of the anterior edge, the center of the femoral head, and the posterior edge of the acetabulum is a straight line (180°) in normal coverage but less in dysplastic hips. This radiographic method provides anatomical information concerning anterior and posterior coverage. Evaluation of 26 hips delineated problems, including possible danger of anterolateral rotation of the acetabulum in the face of posterior deficiency and inadequacy of posterior coverage after Chiari osteotomy.

Sensitivity of spinal cord monitoring to intraoperative events.

Summary: Intraoperative somatosensory evoked potentials in 50 patients were reviewed; each waveform was correlated with intraoperative surgical events and conditions. Twenty-two patients maintained reproducible waveforms and awoke without neurological deficit. Two patients had random waveform changes not correlated with a surgical event and awoke without deficit. Twelve patients showed waveform changes temporally related to circumstances that might endanger cord function; two of these awoke with transient neurological abnormality. Satisfactory waveforms were not obtained from 14 patients. Somatosensory evoked potential monitoring in scoliosis surgery appears to be sensitive, but may not be sufficiently specific; waveform changes do not necessarily indicate objective neurological damage

Does the Outcome of Adolescent Idiopathic Scoliosis Surgery Justify the Rising Cost of the Procedures

BackgroundAs the cost of medical care has steady risen, patients, insurance companies, and the government, have all appropriately questioned the benefit of the care provided versus the cost. Expensive treatments such as surgery for spinal deformity have been especially scrutinized. This article reviews the history of spinal implant usage in deformity surgery, including the benefits of these implants to the patient and also the associated costs. The paper was presented at the One Day Course during the 2009 Pediatric Orthopaedic Society of North America annual meeting in Boston. MethodsA review was conducted regarding the benefits and costs of the care provided to patients as spinal implants became more clinically effective. ResultsCompared with postoperative casting, spinal implants provide better deformity correction and better stability of the fusion mass with resulting lower rates of secondary surgery, mostly because of fewer pseudarthoses. Many of these advantages were achieved with the less-expensive second and third-generation implants. Unfortunately, patient outcomes when the latest, most expensive implants are used are not significantly different from outcomes when older, less-expensive implants are used. ConclusionsAlthough the cost of spinal deformity surgery has risen the benefit to the patient from modern spinal implants has also increased. Nevertheless, patient outcomes have not improved in proportion to the increase in costs. Outcomes from the newest, all pedicle screw constructs are not significantly better than outcomes from the older, less-expensive hybrid constructs. Rising expenses and dramatic variation in the cost of the same implant have led payors, hospitals, and the government to question the value added to the care of the patient. Some implant costs should fall as hospitals use competitive bidding. Surgeons should help their hospitals in the competitive bidding process and declare a willingness to switch to an equivalent system if price differences are excessive. Levels of EvidenceLevel IV Economic Analysis.

Total hip arthroplasty performed during adolescence

Six adolescent patients with 10 severely arthritic hips underwent total hip arthroplasty to regain mobility. Significant intraoperative complications, including difficult intubations, excessive blood loss, and poor fitting components, were encountered. At an average of 7 years 11 months after surgery, 33% of the acetabular components had been revised for symptomatic loosening. In spite of the high failure rates, the psychological and social benefits of improved mobility were substantial.

Using the freehand pedicle screw placement technique in adolescent idiopathic scoliosis surgery: what is the incidence of neurological symptoms secondary to misplaced screws?

Study Design. Retrospective case series. Objective. This study evaluated the incidence of postoperative neurological symptoms after a freehand pedicle screw insertion technique in idiopathic posterior scoliosis surgery. Summary of Background Data. It is generally accepted that pedicle screws can be inserted by a freehand technique in the thoracic and lumbar spine in patients with adolescent idiopathic scoliosis (AIS) with a very low frequency of major complications. The prevalence of clinically significant screw misplacement, with or without the need for revision surgery is less well defined. Methods. Between January 1, 2000, and October 2, 2012, five hundred fifty-nine patients with AIS had thoracolumbar posterior instrumented spine surgery at the Childrens Hospital of Pittsburgh. Each patients chart and radiographs were reviewed and only those with AIS were included. Patients with neuromuscular and syndromic diagnoses were excluded as well as those with congenital or traumatic etiologies, incomplete charts, less than 3 months of follow-up and those without pedicle screws. The records were studied for complaints of radicular pain, neurological deficit, or severe headache that could be indicative of potential screw misplacement. Results. Four hundred eighty-one patients with 5923 pedicle screws met the inclusion criteria. Nine patients (1.9%) developed symptoms and underwent computed tomographic scanning. Six patients were found to have pedicle screw malposition (8 screws) and 3 of these patients underwent revision surgery. Of the 3 revision patients, 2 presented with radicular symptoms (leg pain) and 1 with an orthostatic headache due to cerebrospinal fluid leakage. At the final follow-up, all revision patients had complete symptom resolution. In total, there were 8 symptomatic, misplaced pedicle screws (0.14%) in 6 patients (1.25%). Conclusion. During a 12-year period in a dedicated pediatric orthopedic hospital using the freehand placement technique, the incidence of symptomatic misplaced pedicle screws was exceedingly low. Level of Evidence: 4