Long-term Outcomes of Triple Arthrodesis in Cerebral Palsy Patients.

BACKGROUND: Triple arthrodesis in the appropriately indicated cerebral palsy patient with a painful and/or rigid foot deformity can significantly alleviate pain and improve function. Limited data on long-term outcomes of triple arthrodesis in this patient population exist. In addition, there have been concerns about the long-term consequences of altered biomechanics in these patients on the tibiotalar (ankle) joint. METHODS: We retrospectively reviewed 21 cerebral palsy patients who had undergone triple arthrodesis for a painful and/or rigid foot deformity at our institution with at least 10 years of clinical or radiographic follow-up. Preoperative, and the most recent, clinical evaluations and radiographs were reviewed. In addition, all 21 patients and/or caretakers responded to a questionnaire at the time of this study by means of telephone to assess subjective pain, analgesia use, walking aid necessity, walking distance, and satisfaction with the procedure. RESULTS: In this series of 21 cerebral palsy patients, 5 patients had bilateral surgery, resulting in 26 operative feet. The mean age at the time of surgery was 19.4 years and most recent clinical or radiographic follow-up was 22.1 years postoperatively. Preoperative foot deformity was characterized by hindfoot valgus in 66.7% (14/21) and varus in 33.3% (7/21) of patients. Postoperatively, fusion was achieved in 96.2% (25/26) of feet. At final follow-up, 3 feet (11.5%) demonstrated tibiotalar joint arthritis, 1 (3.8%) had midfoot arthritis, and 10 (38.5%) had residual deformity. Of the total patients, 95.2% (20/21) were satisfied with the outcome and 61.9% (13/21) reported pain-free ambulation. There was no association between eventual functional outcome and preoperative diagnosis, preoperative foot deformity, postoperative tibiotalar joint arthritis, or postoperative residual deformity. CONCLUSIONS: Triple arthrodesis is a surgical option in cerebral palsy patients with painful and/or rigid foot deformities. From this series, successful outcomes can be expected as long as bony union is achieved. The incidence of tibiotalar arthritis is relatively low and not associated with long-term functional outcome. In addition, preoperative and residual postoperative foot deformity is not associated with long-term outcome.

The functional effect of a distal rectus femoris tenotomy in adults with cerebral palsy.

The purpose of this study was to determine the effect of a distal rectus femoris tenotomy on function and gait in adults with cerebral palsy who had diminished knee flexion during swing. A stiff knee gait pattern is commonly seen in individuals with cerebral palsy and frequently leads to tripping and falling. Five subjects, 25-51 years, (34.6±10.3 years) participated in the study; each individual had the surgery after the age of 18. Four of the five subjects underwent bilateral distal rectus femoris tenotomies for a total of nine limbs being studied. Four of the five subjects had a single procedure of a distal rectus femoris tenotomy and one subject also had bilateral adductor tenotomies. All individuals underwent a pre-operative and post-operative, (3.28±1.6 years) three-dimensional gait analysis. Pre-operative gait revealed diminished peak knee flexion and out of phase rectus femoris activity with a quiet vastus lateralis during swing in all subjects. Significant findings after a distal rectus femoris tenotomy included: improved peak swing knee flexion, improved peak stance hip extension, and increased total knee excursion without loss in knee extension strength. During swing, knee flexion angle improved on average 11° which correlated with subjective report of less shoe wear, tripping, and falling due to improved clearance. In conclusion, a distal rectus femoris tenotomy should be considered a surgical option for adults with cerebral palsy and a stiff knee gait pattern to improve mobility, function, and quality of life.

Effect of shoe flexibility on plantar loading in children learning to walk.

BACKGROUND: In a previous pilot study of "cruisers" (nonindependent ambulation), "early walkers" (independent ambulation for 0-5 months), and "experienced walkers" (independent ambulation for 6-12 months), developmental age significantly affected the children's stability when walking and performing functional activities. We sought to examine how shoe structural characteristics affect plantar pressure distribution in early walkers. METHODS: Torsional flexibility was evaluated in four shoe designs (UltraFlex, MedFlex, LowFlex, and Stiff based on decreasing relative flexibility) with a structural testing machine. Plantar pressures were recorded in 25 early walkers while barefoot and shod at self-selected walking speeds. Peak pressure was calculated over ten masked regions for the barefoot and shod conditions. RESULTS: Torsional flexibility, the angular rotation divided by the applied moment about the long axis of the shoe, was different across the four shoe designs. As expected, UltraFlex was the most flexible and Stiff was the least flexible. As applied moment increased, torsional flexibility decreased in all footwear. When evaluating early walkers during gait, peak pressure was significantly different across shoe conditions for all of the masked regions. The stiffest shoe had the lowest peak pressures and the most flexible shoe had the highest. CONCLUSIONS: It is likely that increased shoe flexibility promoted greater plantar loading. Plantar pressures while wearing the most flexible shoe are similar to those while barefoot. This mechanical feedback may enhance proprioception, which is a desirable attribute for children learning to walk.

Long-term followup of total hip arthroplasty in patients with cerebral palsy.

BACKGROUND: Patients with cerebral palsy (CP) are at risk for hip arthrosis secondary to the loss of joint congruity. QUESTIONS/PURPOSES: We asked whether THA relieved pain, improved function, and provided durable improvements. METHODS: We retrospectively identified 56 patients (59 hips) with CP who had THAs for painful hips. Chart review determined the preoperative, postoperative, and current functional levels. All patients or caregivers completed a questionnaire, including a modified Gross Motor Function Classification System mobility scale and qualitative reports of pain and satisfaction. Pain levels were measured on a visual analog scale at three times: preoperative, postoperative, and current. The average age of the patients at the time of surgery was 30.6 years. Minimum followup was 2 years (average, 9.7 years; range, 2-28 years). RESULTS: Pain relief was obtained in all patients. All patients returned to preoperative function (59) and 52 patients returned to prepain functional status (88%). Seven patients underwent acetabular component revisions, and two patients had a femoral stem component revision. The 2-year implant survival was 95%, and 10-year survivorship was 85%. CONCLUSIONS: THA can provide durable relief and improved function in patients with CP with severe coxarthrosis. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Surgical treatment for hip pain in the adult cerebral palsy patient.

Hip subluxation or dislocation in the cerebral palsy population is an acquired condition that can result in pain and limitation of function. The incidence is reported to be from 18 to 59%. Awareness of the factors that cause the problem are essential in order to prevent this condition. Early treatment consists of appropriate muscle lengthening or releases, varus rotation hip osteotomies and in some cases pelvic osteotomies to provide acetabular coverage for the femoral head. For painful hip subluxation or dislocation with arthrosis in the adolescent or adult salvage procedures such as hip arthrodesis, valgus osteotomy, proximal femoral resection, or total hip arthroplasty have all been done to relieve pain. The author recounts his experience of the surgical management of the hip in the individual with cerebral palsy.

Differential effects of alendronate treatment on bone from growing osteogenesis imperfecta and wild-type mouse.

Bisphosphonates have been reported to decrease the number of fractures in children with osteogenesis imperfecta (OI). The current study sought to further explore bisphosphonate-associated bone changes in OI by investigating the effects of alendronate (ALN) treatment on bone mechanical and material properties in osteogenesis imperfecta (oim/oim) and wild-type (+/+) mice treated with 26-73 microg kg(-1) day(-1) of ALN for 8 weeks via subcutaneously implanted pumps. Femoral three-point bend tests to evaluate cortical bone were combined with geometric and material density analysis. Cortical and trabecular architecture of metaphyseal bone were histomorphometrically evaluated and material density assessed by quantitative backscattered electron imaging (qBEI). For the cortical oim/oim bone, which revealed principally inferior biomechanical properties compared to +/+ bone, ALN neither improved cortical strength or any other mechanical property, nor affected cortical width (Ct.Wi.) or material density. In contrast, for the +/+ mice, bone strength was enhanced (+22%, P < 0.05) though coupled with increased brittleness (+28%, P < 0.05). This mechanical improvement was associated with an increase in Ct.Wi. (+17.3%, P = 0.02) and a reduction in heterogeneity of cortical mineralization (Ca(Width), -4%, P = 0.04). In the metaphysis, ALN raised cancellous bone volume (BV/TV) significantly in oim/oim as well as in +/+ mice (+97%, P = 0.008 and +200%, P < 0.0001, respectively). This occurred without any change in either material density or trabecular thickness (Tb.Th.) in the oim/oim mice, while in the +/+ mice, material density increased slightly but significantly (+3%, P = 0.004), and Tb.Th. increased by 77% (P < 0.0001). Taken together, these results illustrate the differential effects of ALN on oim/oim vs. +/+ bone, as well as on specific skeletal sites, i.e., cortical vs. trabecular bone. ALN augmented the mechanical, geometrical, and material properties of +/+ cortical and trabecular bone, while the only observable improvement to the oim/oim bone was increased cancellous bone volume. This suggests that in this mouse model of OI, the previously demonstrated bisphosphonate-associated reduction in fractures is primarily attributable to increased metaphyseal bone mass.

Relationships among musculoskeletal impairments and functional health status in ambulatory cerebral palsy.

Orthopedic surgery for patients with cerebral palsy addresses motion impairments, assuming that this will improve motor function. This study evaluates the relationships among clinical impairment measures with standardized assessments of function and disability as an initial step in testing this assumption. A total of 129 ambulatory children and adolescents across six institutions participated in a prospective evaluation that consisted of passive motion and spasticity examination of the lower extremities, three-dimensional gait temporal-spatial and kinematic analysis, and administration of the Gross Motor Function Measure (GMFM) and the Pediatric Outcomes Data Collection Instrument (PODCI). The analysis found that isolated impairment measures of motion and spasticity were only weakly related to motor function in cerebral palsy and even when averaged across multiple joints yielded no more than a fair correlation with functional scores, nor did a combination of impairments emerge that could predict substantial variance in motor function. These findings suggest that caution should be exercised when anticipating functional change through the treatment of isolated impairment and that addressing multiple impairments may be needed to produce appreciable effects.

Proximal femoral varus rotation osteotomy in cerebral palsy: a prospective gait study.

This prospective study examined the kinematic and temporal/spatial effects of proximal femoral varus rotation osteotomy (VRO) on the gait of individuals with cerebral palsy from preoperative to 1-year postoperative status. Participants were a consecutive sample of 37 individuals (14 males, 23 females). The analysis consisted of three-dimensional kinematics, temporal/spatial measures, and functional status. A curve representing the difference between the preoperative and 12-month postoperative conditions was calculated for each joint motion. Ninety-five percent confidence intervals were calculated about the mean difference curves using a bootstrapping technique. VRO resulted in improved cosmesis and objective improvement in gait, including a statistically significant increase in hip external rotation and hip extension, a decrease in anterior pelvic tilt, and an increase in knee extension strength. The use of confidence bands to identify surgical outcomes with respect to kinematic variables has enormous value for patients and professionals. Long-term follow-up is needed to see if the aforementioned gains improve.

Quality of life in osteogenesis imperfecta.

The purpose of this study was to quantify the physical and mental health of a diverse adult cohort of patients with osteogenesis imperfecta (OI) utilizing a validated health self-assessment questionnaire (SF-36). In addition, a specific demographic questionnaire and a functional questionnaire were utilized to assess more specifically the physical limitations imposed by osteogenesis imperfecta in adulthood. The results of the SF-36 revealed significantly lower physical function scores compared to the U.S. adult norms. However, the SF-36 mental component scores were equal to the U.S. adult norms. The demographic questionnaire revealed high levels of educational achievement, as well as employment, despite significant physical impairments. The functional questionnaire clearly demonstrated limitations mostly related to ambulation.