James G. Gamble

Energy expenditure index of walking for normal children and for children with cerebral palsy.

Energy expenditure indices (EEI) based on oxygen uptake and heart rate were used to compare the economy of walking at various speeds by normal and cerebral‐palsied children. At low walking speeds, EEI values were high, indicating poor economy. At higher speeds the EEI values decreased until a range of maximum economy was reached. For normal children who were capable of walking beyond this range at higher speeds, the EEI increased again. This pattern was noted for both oxygen‐uptake and heart‐rate indices. Mean EEI values based on oxygen uptake and heart rate for normal children were significantly lower and occurred at faster walking speeds than values for children with cerebral palsy. EEI based on either oxygen uptake or heart rate can be used clinically to provide objective information to help evaluate the influence on gait function of surgical intervention, ambulatory aids or orthotics.

Postural balance in children with cerebral palsy

Postural control deficits have been suggested to be a major component of gait disorders in cerebral palsy (CP). Standing balance was investigated in 23 ambulatory children and adolescents with spastic diplegic CP, ages 5 to 18 years, and compared with values of 92 children without disability, ages 5 to 18 years, while they stood on a force plate with eyes open or eyes closed. The measurements included center of pressure calculations of path length per second, average radial displacement, mean frequency of sway, and Brownian random motion measures of the short-term diffusion coefficient, and the long-term scaling exponent. In the majority of children with CP (14 of 23) all standing balance values were normal. However, approximately one-third of the children with CP (eight of 23) had abnormal values in at least two of the six center of pressure measures. Thus, mean values for path length, average radial displacement, and diffusion coefficient were higher for participants with CP compared with control individuals with eyes open and closed (p<0.05). Mean values for frequency of sway and the long-term scaling exponent were lower for participants with CP compared with control participants (p<0.05). Increased average radial displacement was the most common (nine of 23) postural control deficit. There was no increase in abnormal values with eyes closed compared with eyes open for participants with CP, indicating that most participants with CP had normal dependence on visual feedback to maintain balance. Identification of those children with impaired standing balance can delineate factors that contribute to the patients gait disorder and help to guide treatment.

Energy cost of walking in normal children and in those with cerebral palsy: comparison of heart rate and oxygen uptake.

The rate of oxygen uptake can be used to assess energy expenditure during walking, but the necessary intrumentation is cumbersome, expensive, and usually unavailable in the clinical setting. Heart rate is an easily measured parameter, but its use as an index of energy expenditure in children has not been validated previously. We found that the relationship between oxygen uptake and heart rate was linear throughout a wide range of walking speeds for both children with cerebral palsy and normal children. There was no significant difference between the slope or the y-intercept of the lines for the two groups. These findings validate the use of heart rate as an index of energy expenditure for normal children and for children with cerebral palsy.

The energy expenditure index : a method to quantitate and compare walking energy expenditure for children and adolescents

We used heart rate and walking speed to calculate an energy expenditure index (EEI), the ratio of heart rate per meter walked, for 102 normal subjects, age 6-18 years. Heart rate was measured at self-selected slow, comfortable, and fast walking speeds on the floor and on a motor-driven treadmill. At slow walking speeds (37 +/- 10 m/min) the EEI was elevated (0.71 +/- 0.32 beats/m), indicating poor economy. At comfortable speeds (70 +/- 11 m/min) the EEI values decreased to the maximum economy (0.47 +/- 0.13 beats/m). At fast speeds (101 +/- 13 m/min), the EEI increased (0.61 +/- 0.17 beats/m), indicating poor economy relative to comfortable speeds. A graph of the EEI versus walking speed provides a way to evaluate and compare energy expenditure in a clinical setting.

Chronic Recurrent Multifocal Osteomyelitis: A Distinct Clinical Entity

Summary: We reviewed the cases of five children with the diagnosis of chronic recurrent multifocal osteomyelitis (CRMO) and compared and contrasted them to 11 cases of subacute osteomyelitis. Significant differences were found between these two groups in the number of cases with positive biopsy cultures, number of clinical episodes, and number of bones involved. In CRMO, cultures are negative, and recurrent clinical episodes involve different bones at different times. The data indicate that CRMO is a distinct clinical entity, different from subacute osteomyelitis; it is a benign, self-limiting inflammatory disease of bone, and no chronic problems have occurred as a result of CRMO. Restraint in antibiotic treatment and in performing repeated biopsies is indicated in CRMO.

Arthropathy of the ankle in hemophilia.

Seventy-five patients who had hemophilia were followed clinically and roentgenographically to assess the prevalence of hemarthrosis and the prevalence and severity of arthropathy of the ankle. The mean age of the patients at the time of follow-up was twenty-two years and seven months. The patients were divided into four age-groups: less than ten years (eleven patients), ten to nineteen years (twenty-one patients), twenty to thirty years (twenty-four patients), and more than thirty years (nineteen patients). Intra-articular bleeding occurred more frequently in the joints of the lower extremities than in the joints of the upper extremities. During the second decade of life, hemarthroses occurred more often in the ankle than in the knee. A history of recurrent bleeding into the ankle joint, chronic synovitis, and overgrowth of the medial portion of the distal tibial epiphysis was associated with an early onset of arthropathy. In older patients, compression arthrodesis of the ankle joint was helpful in eliminating pain, recurrent bleeding, and equinus deformity.

Enzymatic adaptation in ligaments during immobilization

Ligaments are a composite of fibroblasts and collagen in a proteoglycan matrix. Seventy-five percent of the organic solid is collagen and 23% is proteoglycan. Fibroblasts are responsible for the overall composition of the ligament, that is the synthesis and the degrada tion of macromolecular components. Like muscle and bone, ligaments are dynamic, undergoing hypertrophy with exercise and atrophy with immobilization. This paper reviews the structure and composition of liga ments and discusses the cellular events responsible for atrophy of ligaments with immobilization. As an exper imental model, one knee of New Zealand White rabbits was immobilized with a pin. After 2, 4, and 8 weeks of immobility, the medial collateral ligaments were isolated and enzyme analysis was performed. Gross and micro scopic changes were apparent after 2 weeks. As for enzyme changes, lactic dehydrogenase and malic de hydrogenase decreased in activity. The lysosomal hy drolases responsible for glycosaminoglycan degrada tion increased in activity, suggesting that enzymatic adaptations mediate the physical and chemical changes in the ligament. The cells switch from an anabolic synthetic state to a catabolic, degradative state during immobility. It would seem from the biochemical view point that, whenever possible, cast-bracing and func tional splints may be preferable to rigid plasters in many sports-related ligamentous injuries.

Complications of intramedullary rods in osteogenesis imperfecta: Bailey-Dubow rods versus nonelongating rods.

Summary: Twenty-nine patients with osteogenesis imperfecta underwent 108 intramedullary roddings with 42 Bailey-Dubow rods and 66 nonelongating rods. The average age at insertion of the first rod was 5 years; average follow-up was 3.1 years (range 1–9 years). The overall complication rate was 60%—69% for Bailey-Dubow rods and 55% for nonelongating rods. Forty-seven percent of bones receiving rods required reoperation. Nonelongating rods had a 29% reoperation rate and a 24% replacement rate; Bailey-Dubow rods had a 19% reoperation rate and a 12% replacement rate.

Simultaneous correction of pelvic obliquity, frontal plane, and sagittal plane deformities in neuromuscular scoliosis using a unit rod with segmental sublaminar wires: a preliminary report.

Ten patients with neuromuscular scoliosis and pelvic obliquity had segmental spinal instrumentation using a unit Luque rod with sublaminar wires and fixation into the pelvis. Nine of the 10 patients also had anterior spinal fusion without instrumentation before the posterior procedure. Average preoperative pelvic obliquity was 42° which was corrected to 6° (82% correction). Average preoperative scoliosis was 92°, which was corrected to 16° (81% correction). Complications included a wound hematoma in one patient and a superficial wound dehiscence in another. There have been no pseudarthroses or hardware failures to date. Excellent correction of the pelvic obliquity and the spinal curve in neuromuscular scoliosis can be obtained with use of a unit rod and without use of anterior instrumentation.

Hip Adductor Injury in Competitive Swimmers

Methods The authors conducted a survey of 296 competitive swimmers to assess the incidence and importance of interfering groin pain in breaststroke swimmers. Results Breaststroke swimmers were more likely to have current groin pain (6.92%) than individual medley swimmers who did not compete in pure breaststroke events (0, P= 0.015). Breaststroke swimmers (42.7%) were also more likely than individual medley swimmers (21.5%, P= 0.000622) or nonbreaststroke, nonindividual medley swimmers (5.8%, P= 0.00000311) to have been unable to train breaststroke in practice during the past year due to groin injury. Conclusion Results indicate that breaststroke swimmers are at significant risk of groin injury, groin injury is positively correlated with increased magnitude of breaststroke training, and groin injury may prevent participation in practices and competitions.