Richard Haynes

The Pediatric Orthopaedic Society of North America Pediatric Orthopaedic functional health questionnaire: An analysis of normals

Several questionnaires have been developed in an attempt to measure real-life functional levels of pediatric orthopaedic patients. One in particular was developed by the Pediatric Orthopaedic Society of North America (POSNA) in 1994. This POSNA instrument yields four functional assessment scores, a global function score, and a happiness score (each having a possible range from 0 to 100). In this study, the POSNA questionnaire was administered to the parents of 57 normal children and 27 normal adolescents to determine how normal respondents can be expected to score. Means, standard deviations, and other statistics were derived for the functional scores. It was concluded that normal children should respond quite high on all the scores, possibly 100. These results allow us to understand that a child scoring in the low 80s or less is functioning at a different level than the normal child.

Osteology of the pediatric skull. Considerations of halo pin placement.

Study Design Computed tomography scans of the heads of 48 normal children were measured for skull thickness in areas of routine halo pin placement. The thickest and thinnest areas were noted. Objectives The head computed tomography scans were measured to identify consistently thin areas in the pediatric skull that should be avoided when pins are placed. Summary of Background Data Complications of halo pin placement in children are common, including loosening and dislodgment, infection and penetration. Methods Normal head computed tomography scans of 48 normal children, 10 years old and under, were divided into four age groups. Total skull thickness was measured in five areas at the level of halo insertion. Results There was a trend toward increasing skull thickness with age. There was a large variation in skull thickness at each area within and between age groups. None of the standard pin sites was consistently thicker. Even up to 10 years of age, the average thinnest area was only 1.9 mm. Conclusions There is no “safe area” for halo pin placement in the pediatric skull. Limited preoperative head computed tomography scans are recommended to determine safe areas for pin placement.

The Pediatric Outcomes Data Collection Instrument (PODCI) and functional assessment of patients with unilateral upper extremity deficiencies.

The Pediatric Outcomes Data Collection Instrument (PODCI) questionnaire was used to quantify functional abilities of a group of unilateral upper extremity deficiency (U-UED) patients and compare them with “normal” control children. Sixty-four consecutive patients with U-UED were assessed. Parents and adolescent (ages 11-21) patients responded. Underlying diagnosis, amputation level, and type of prosthesis were recorded. Scores were compared for congenital versus traumatic etiologies for patients with various amputation levels, and for patients using prostheses versus those not using prostheses. In both parent and patient responses, PODCI scores were significantly lower than “normal” for upper extremity function and sports. Scores were similar for congenital and acquired amputees. Responses from adolescent patients showed progressively decreasing scores for upper extremity, transfers, sports, and global function with progressively proximal amputation levels. Patients using prostheses with different terminal devices did not significantly differ. Parent responses for prosthesis wearers showed lower comfort/pain scores (ie, increased pain) than non-prosthesis wearers, but no significant differences in function, including upper extremity function.

Rectus and hamstring surgery in cerebral palsy: A gait analysis study of results by functional ambulation level

The purpose of this study is to determine if children more severely involved with cerebral palsy respond as well to rectus transfer and hamstring surgery as those with less severe involvement. Ninety-nine children were classified as independent community ambulators, crutch/walker-dependent community ambulators, or household/exercise ambulators. Maximum knee extension in stance and total range of knee motion in gait increased following surgery in all groups. Peak knee flexion in swing was maintained in the independent group only, but timing of knee flexion in swing improved in all groups. All groups showed increases in stride length, and the household/exercise group also showed an increase in walking speed. Four of 39 crutch/walker-dependent community ambulators and 13 of 21 household/exercise ambulators progressed to the next higher functional ambulation group.

Hemiepiphysiodesis for the Correction of Angular Deformity About the Knee

Background: It is generally accepted that the presence of angular deformity about the knee that persists into the preadolescent years will not correct spontaneously. The goal of this study was to review our experience with hemiepiphysiodesis and physeal stapling for the correction of angular deformity to establish the efficacy of these procedures and to determine their indications and the rate of correction. Methods: A retrospective review of 48 patients undergoing hemiepiphysiodesis or physeal stapling about the knee was performed. Patients were included if they had at least 2 years of documented follow-up without an osteotomy. Results: The average follow-up was 30.4 months (range, 24-52months). Genu varum was identified in 33 patients, genu valgum in 14 patients, and a windswept deformity in 1. Of the 52 limbs with genu varum, 35 were secondary to Blount disease. The group with genu varum unrelated to Blount disease presented a change in the mechanical axis from a mean of −32 degrees at surgery to a mean of − 13degrees. The patients with Blount disease presented a change in the mechanical axis from a mean of −19 degrees at surgery to a mean of −16 degrees. The group with genu valgum presented a change in the mechanical axis from a mean of 20 degrees at surgery to a mean of 2 degrees. Conclusions: Hemiepiphysiodesis is an effective means for correcting angular deformity about the knee in skeletally immature patients with both genu valgum and genu varum, so long as the genu varum is unrelated to Blount disease. Hemiepiphysiodesis is effective in preventing the progression of deformity in patients with Blount disease. Level of Evidence: Therapeutic-Level IV.

Functional significance of bone density measurements in children with osteogenesis imperfecta

BACKGROUND The treatment of osteogenesis imperfecta has been directed at improvement of bone mineral density, yet the importance of bone mineral density in predicting functional and clinical outcome in this patient population has not been demonstrated. We used a validated functional outcome measure to identify the relationship between bone mineral density and physical function in children with osteogenesis imperfecta, and we also evaluated the relationship of bone mineral density to the rate of surgery and fracture in patients with osteogenesis imperfecta. METHODS Twenty patients (age range, four to seventeen years) with osteogenesis imperfecta who had undergone bone mineral densitometry as measured by dual x-ray absorptiometry of the lumbar spine, wrist, and proximal aspect of the femur between November 1999 and April 2001 were retrospectively analyzed. Functional outcome was measured with use of the Pediatric Outcomes Data Collection Instrument. These questionnaires were completed by the parents of all twenty patients and, in addition, by fifteen patients in the study who were between the ages of eleven and eighteen years. Fracture and surgery rates were calculated on the basis of the number of documented fractures and surgical procedures that the patient had had from the time of the initial presentation until the time of the latest follow-up visit. RESULTS There were significant relationships between the bone mineral density of the lumbar spine and the scores obtained on the parent-completed questionnaires with regard to upper-extremity functioning (r = 0.57, p < 0.01), transfers and basic mobility (r = 0.55, p = 0.01), sports and physical functioning (r = 0.55, p = 0.01), and global functioning (r = 0.60, p < 0.004). There were also significant relationships between the bone mineral density of the wrist and the scores obtained on the child-completed questionnaires with regard to upper-extremity functioning (r = 0.82, p < 0.01), sports and physical functioning (r = 0.76, p < 0.01), and global functioning (r = 0.83, p = 0.001). There were significant negative relationships between the bone mineral density of the lumbar spine and the rate of fractures (r = -0.69, p < 0.001) and the bone mineral density of the lumbar spine and the rate of surgery (r = -0.60, p < 0.01). CONCLUSIONS There is a relationship between bone mineral density and the functional outcome, rate of fracture, and rate of surgery in patients with osteogenesis imperfecta. Bone mineral density appears to be an indicator of disease severity and may be predictive of long-term functional outcome. To establish specific guidelines for treatment, more data on normative bone-mineral density in children with osteogenesis imperfecta will be needed.

A prospective evaluation of the WeeFIM in patients with cerebral palsy undergoing orthopaedic surgery.

Purpose: Although frequently used in pediatric rehabilitation settings, the WeeFIM has not been tested in surgical pediatric orthopaedic patients. Methods: The WeeFIM was administered to patients with surgical cerebral palsy at defined intervals preoperatively and at both 6 and 12 months postoperatively. The age-adjusted change scores from baseline to follow-up were tested both parametrically and nonparametrically. Results: Four hundred sixty-eight patients had baseline evaluations. There were 161 six-month follow-up assessments and 108 twelve-month follow-up assessments. The baseline WeeFIM was able to separate children with different patterns of cerebral palsy. Hemiplegic patients had higher scores than diplegic and tetraplegic patients. Overall age-adjusted scores were improved at both 6 (mean increase 2.0) and 12 months (mean increase 2.2). The instrument showed significant ceiling effects for diplegic and hemiplegic patients with lower or upper extremity surgery and limited responsiveness for lower extremity surgery in tetraplegic patients. Parametrically, it showed improvements in mobility for both rhizotomy and tetraplegic upper extremity surgery. Nonparametric tests were not significant for rhizotomy mobility improvement. Conclusions: Although the WeeFIM adequately reflects the severity of neurological involvement in pediatric orthopaedic patients with cerebral palsy, it has a significant ceiling effect in diplegic and hemiplegic patients limiting responsiveness and lacks content validity for tetraplegic patients. The instrument may have some use in tetraplegic patients with upper extremity surgery and in rhizotomy patients. We recommend against its general use for orthopaedic surgery in patients with cerebral palsy lower extremity or spine surgery and in hemiplegic patients with upper extremity surgery.

Flexion and extension cervical MRI in a pediatric population

Cervical spine flexion/extension magnetic resonance imaging (MRI) was used in 17 pediatric patients (age, 9 months to 12 years) for assessment of spinal cord compression secondary to instability. Nine of these patients had cord compression demonstrated on flexion/ extension MRI (flexion and extension, five; flexion, three; extension, one). These nine patients all had neurologic manifestations and underwent surgery. Patients without spinal cord compression on MRI did not demonstrate any neurologic manifestations. Flexion/extension MRI of the cervical spine was very useful in selecting appropriate patients for arthrodesis and determining the necessity for concurrent anterior or posterior decompression.

Pin removal in slipped capital femoral epiphysis : the unsuitability of titanium devices

In an effort to predict which slipped capital femoral epiphysis fixation devices might cause fewer retrieval problems, 27 consecutive implant-retrieval procedures were reviewed, and mechanical tests using many currently available devices were performed. Problems occurred with both stainless steel and titanium devices if implanted for > 1 year. This tendency for increased problems was statistically significant for the titanium group, and analysis of a retrieved titanium screw showed evidence of osseointegration (direct bone-metal contact at > 90% of the interface) using backscattered image scanning electron microscopic analysis. These clinical data and data from mechanical testing suggest that stainless steel screws or trocar-tipped Steinmann pins are better suited for fixation of slipped capital femoral epiphysis.

A biomechanical comparison of Gardner-Wells tongs and halo device used for cervical spine traction.

Summary of Background Data Unstable cervical spine fractures and dislocations are often reduced by the application of axial traction using a halo or Gardner-Wells tongs. Failure of tong or halo attachment can cause substantial morbidity and usually occurs at the pin-bone interface. Institutions commonly clean and reuse tongs. The effect of tong wear on pullout strength and the strength of the halo used as a traction device have not been documented. Methods A skull model biomechanically similar to human calvarium was used to compare the axial pullout strengths of four sets of new tongs, three sets of rarely used tongs, and one set of heavily used tongs, as well as a standard four-pin halo. Results The pullout strength of tongs tightened to the manufacturers recommended level appeared to decrease with increased use. Measurement of the pin force generated by each set of tongs and of the spring constant of each spring, as well as inspection of the tongs after testing, suggested that the decrease in pullout strength may be partly attributable to spring and/or pin wear. The pullout strength of the halo or of the new or slightly used tongs but not the heavily used tongs exceeded the maximum weight used clinically in cervical spine traction. Conclusion The data suggest that consideration be given to replacement or recalibration of heavily used tongs.