Analysis of factors affecting development of carpal tunnel syndrome in patients with Hurler syndrome after hematopoietic cell transplantation.

Children with Hurler syndrome (mucopolysaccharidosis type IH (MPSIH)) have skeletal, joint and soft tissue abnormalities that may persist or progress after hematopoietic stem cell transplantation (HSCT). We report our single center experience with development of carpal tunnel syndrome (CTS) in 43 children with MPSIH after HSCT. Twenty-three children (59%) developed CTS following HSCT; 19 of the 39 children with enzyme activity in the normal or heterozygous range developed CTS (49%), whereas all four children with low heterozygous or absent enzyme activity developed CTS after HSCT. Fourteen of 19 related donor marrow recipients, eight of 19 of those receiving an unrelated donor graft and one of five unrelated cord blood recipients developed CTS. The mean age at surgical release was 4.8 years. With each year increase in age at HSCT, there was a 55% increased risk. Age and enzyme activity after HSCT were significant factors in the development of CTS. Transplantation by 2 years of age reduced the risk of developing CTS by 46%; higher enzyme activity led to a 78% reduction in the risk of developing CTS. However, children transplanted for MPSIH remain at risk for the development of CTS, and should be monitored on an ongoing basis by nerve conduction velocity testing.

Indirect reduction and percutaneous fixation versus open reduction and internal fixation for displaced intra-articular fractures of the distal radius: a randomised, controlled trial.

A total of 179 adult patients with displaced intra-articular fractures of the distal radius was randomised to receive indirect percutaneous reduction and external fixation (n = 88) or open reduction and internal fixation (n = 91). Patients were followed up for two years. During the first year the upper limb musculoskeletal function assessment score, the SF-36 bodily pain sub-scale score, the overall Jebsen score, pinch strength and grip strength improved significantly in all patients. There was no statistically significant difference in the radiological restoration of anatomical features or the range of movement between the groups. During the period of two years, patients who underwent indirect reduction and percutaneous fixation had a more rapid return of function and a better functional outcome than those who underwent open reduction and internal fixation, provided that the intra-articular step and gap deformity were minimised.

Musculoskeletal function assessment: reference values for patient and non-patient samples.

Although researchers and clinicians are encouraged to use health-status questionnaires to evaluate, monitor, and modify care, their use is hindered by the lack of reference values. Without reference values, it is difficult to interpret or evaluate questionnaire scores. In this paper, we present reference values for the Musculoskeletal Function Assessment, a 101-item health-status questionnaire designed and validated for patients with a broad range of musculoskeletal disorders. We describe reference values for two samples: non-patients (n = 123) and patients with isolated extremity injuries (n = 274). For the non-patient sample, descriptive statistics are presented by age and gender, measured at one point in time. For the patient sample, descriptive statistics are provided for seven Orthopaedic Trauma Association/AO diagnostic groups, measured at two points in time. Reference values for changes in the Musculoskeletal Function Assessment total score are described for patients 3 and 9 months and 6 and 12 months after injury. The total scores by post-injury interval, across the diagnostic groups, are significantly better at follow-up than at baseline (p = 0.00). Reference values for changes in total scores are also described in terms of these diagnostic groups across post-injury intervals. Musculoskeletal Function Assessment total scores for Orthopaedic Trauma Association/AO diagnostic groups are significantly better at follow-up than at baseline (p < 0.03). Changes in the total score are also tested for responsiveness with use of standardized response means. Large effects are demonstrated for patients completing the Musculoskeletal Function Assessment at 3 and 9 months (1.03), and small effects are demonstrated for those completing it at 6 and 12 months (0.49). Moderate and large effects are demonstrated for Orthopaedic Trauma Association/AO diagnostic groups across post-injury intervals.

Development of a musculoskeletal extremity health status instrument: the Musculoskeletal Function Assessment instrument.

Despite an increasing reliance on the use of health status measures to assess and evaluate medical care, no single instrument is currently available for use with the broad range of patients with musculoskeletal disorders of the extremities that is commonly seen in clinical practice. In this paper, we report on the development of the Musculoskeletal Function Assessment instrument, a 100-item self reported health status instrument that is designed to meet this need. The instrument was developed in two phases. During the first phase, items were selected on the basis of interviews with 135 patients and 12 clinicians and from reviews of existing health status instruments. The items then were grouped into categories. During the second phase, the instrument was tested for reliability and content validity using a sample of 327 patients with one of five musculoskeletal disorders of the upper and lower extremities (fractures, soft-tissue injuries, repetitive motion disorders, osteoarthritis, and rheumatoid arthritis). The patients were selected from both community and academic sites. Content validity also was demonstrated, based on a review of item selection procedures, expert opinion, and the distribution of scores on the instrument.

Musculoskeletal Function Assessment instrument: criterion and construct validity.

The Musculoskeletal Function Assessment (MFA) instrument, a health status instrument with 100 self-reported health items, was designed for use with the broad range of patients with musculoskeletal disorders of the extremities commonly seen in clinical practice. In this paper, we report on its criterion and construct validity. Criterion validity was tested against physicians' ratings of patient functioning (e.g., upper functioning, lower functioning, daily activities, recreational functioning, emotional adjustment, and overall functioning) and standard clinical measures (e.g., grip strength, walking speed, fine motor skills, knee and elbow strength, and range of motion). Significant correlations (p < or = 0.05) between its scores, physicians' ratings, and clinical measures support the MFA's criterion validity. Construct validity was demonstrated against existing measures of health status (e.g., measures of lower and upper mobility, activity level and satisfaction, health status, social support, pain, emotional status, and quality of life), in accordance with clinical hypotheses about the effect of musculoskeletal disorders on functioning (e.g., type and number of problems, severity of illness or injury, and comorbidities) and by an analysis of demographic characteristics (e.g., sex, education, income, health insurance, and employment) against the MFA scores. Discriminant construct validity was supported in an analysis of MFA scores by patient disease groups (p < or = 0.01).

Comparison of the Musculoskeletal Function Assessment questionnaire with the Short Form-36, the Western Ontario and McMaster Universities Osteoarthritis Index, and the Sickness Impact Profile health-status measures.

We compared the reliability, validity, and responsiveness of the Musculoskeletal Function Assessment (MFA) questionnaire with those of three commonly used health-status measures: the Short Form-36 (SF-36), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Sickness Impact Profile (SIP). The MFA, like the other health-status measures, demonstrated good reliability (intraclass correlation coefficients of more than 0.70), good sensitivity and specificity (more than 70 per cent), good criterion validity that correlated with physicians' ratings (p < 0.01), and good construct validity that correlated with the characteristics of the patients (p < 0.01). It also demonstrated better content validity than the other questionnaires, with no ceiling or floor effects for the total score. In addition, it was more responsive than the SF-36; for eight of the eleven comparisons, it was more efficient (relative efficiency of more than 2.00) in measuring changes in function between the baseline values and the values determined at the latest follow-up evaluation. These findings suggest that the MFA can be used to assess the health status of patients who have a musculoskeletal disorder.

Short musculoskeletal function assessment questionnaire: validity, reliability, and responsiveness.

BACKGROUND: A short questionnaire on functional status was designed for use in community-based outcome studies and in the management of individual patients who have musculoskeletal disease. As most musculoskeletal care is delivered in community practices, short, validated instruments are necessary to perform clinical studies on the effectiveness of treatment in this setting. METHODS: A forty-six-item questionnaire was created as an extension of the work to develop the longer, 101-item Musculoskeletal Function Assessment (MFA) questionnaire. The Short Musculoskeletal Function Assessment (SMFA) questionnaire consists of the dysfunction index, which has thirty-four items for the assessment of patient function, and the bother index, which has twelve items for the assessment of how much patients are bothered by functional problems. The SMFA questionnaire was evaluated for reliability, validity, and responsiveness in a population of 420 patients who had a musculoskeletal disease or injury. RESULTS: The SMFA questionnaire demonstrated excellent internal consistency and stability, with most values greater than 0.90. Content validity for the dysfunction and bother indexes was supported with very little skew (less than 1.00), few ceiling effects (less than 5 percent), and no floor effects. Convergent validity was supported with significant correlations between the SMFA dysfunction and bother indexes and the physicians' ratings of patient function (for example, activities of daily living, recreational and leisure activities, and emotional function [rho > or = 0.40]) and standard clinical measures (for example, grip strength and walking speed [r > or = 0.401). Convergent and discriminant construct validity of the SMFA indexes were demonstrated (p < 0.01) in comparisons with clinical, demographic, Short Form-36 (SF-36), and life-change data. The responsiveness of the SMFA questionnaire to change over time was demonstrated with standardized response means ranging from moderate (0.76) to large (-1.14) for patients who had changes in health status. CONCLUSIONS: The SMFA questionnaire may be used for clinical assessments of the impact of treatment in groups of patients who have musculoskeletal disease or injury. It also may be used in clinical settings to provide reliable and valid assessments of the health status of an individual patient.

Influence of recombinant human erythropoietin on hematological and hemostatic parameters with special reference to microhemolysis.

Twenty chronic hemodialysis patients with renal anemia (hematocrit < 25%) received recombinant human erythropoietin (40 IU/kg body weight 3 x weekly) intravenously after each dialysis. Prior to and at 4, 8 and 12 weeks after commencement of erythropoietin therapy, hematocrit together with hemostasis and microhemolysis parameters were determined. There were significant increases in hematocrit, platelet count and platelet retention, but a significant fall in the initial clearly prolonged bleeding time. Free plasma hemoglobin likewise increased. Conversely, lactate dehydrogenase, prothrombin time, fibrinogen, antithrombin III activity, protein C activity and protein S concentration were all unaltered. The positive effect on bleeding time and platelet retention is most probably caused by an increase in adenosine diphosphate due to the hematocrit-dependent rise in the blood shear stress via physiologic microhemolysis (raised free plasma hemoglobin).

Disseminated candidiasis: a comparison of two immunologic techniques in the diagnosis.

Eighty-five subjects were tested for the presence of circulating candidal antigen (CAg) and anti-candidal antibody (CAb) using both an enzyme immunoassay (ELISA) and counterimmunoelectrophoresis (CIE). The 72 studied controls included laboratory volunteers; hospitalized patients without evidence of infection; febrile hospitalized patients without evidence of candidiasis; and patients with superficial candidiasis and candiduria. The control subjects were compared with 13 patients with proven disseminated candidal infection (disease prevalence = 15%). The ELISA CAb test was of greater individual sensitivity (92%) in separating patients with systemic candidiasis from all controls combined than the ELISA CAg, CIE CAg, or CIE CAb test (61%, 15%, 69%, respectively). The CIE CAg test, though specific (100%), was insensitive. Sensitivity, specificity, and predictive values were generally enhanced by employing combinations of tests. Sera from patients with disseminated candidiasis were much more likely to yield a positive result by two or more serologic tests than were control sera (p = less than 0.0004). The sensitivity of combinations ranged from 15% to 92%. The specificity of combinations ranged from 21% to 100%. The predictive value positive of combinations test ranged from 40% to 100%. Predictive value negative of combinations ranged from 69% to 98%. Patients with a variety of superficial and deep candidal infections apparently have detectable circulating CAb and/or CAg. The ELISA CAb test was superior to the other tests in identifying patients with disseminated candidiasis. Combinations of serologic tests may be superior to individual tests in the diagnosis or exclusion of serious disease due to Candida albicans.

Living with artificial grass: a knowledge update. Part 1: Basic science.

Part I of this two part study reviews the development and characteristics of artificial grass, and the influence of this surface on the American football player. Artificial grass was initially developed to provide city children with increased play space and thus enable them to maintain a fitness level equal to their peers in more rural locales. Today, artificial grass fields allow for increased use when field availability is limited, or for a grass substitute where grass will not grow. However, epidemiologic studies suggest that there is an increased risk of lower extremity injury to the football athlete playing on an artificial grass field. By reviewing available studies, a knowledge base can be formed that can serve to direct future investigations concerning the influence of artificial grass surfaces and injury and, ultimately, how that influence can be affected.

Living with artificial grass: a knowledge update. Part 2: Epidemiology.

Part 2 of our study evaluated the effect of artificial grass on the athletes that play on it. In this section we have reviewed the epidemiological studies that have evaluated the influence that artificial grass has on the frequency and site of injury to American football players. From this review we have concluded that play and practice on an artificial surface is probably responsible for an increase in the relative risk of injury to the lower extremity of the participants. However, it is evident that more well controlled studies are necessary to completely clarify this issue.

Noncontact anterior cruciate ligament injuries: risk factors and prevention strategies.

An estimated 80,000 anterior cruciate ligament (ACL) tears occur annually in the United States. The highest incidence is in individuals 15 to 25 years old who participate in pivoting sports. With an estimated cost for these injuries of almost a billion dollars per year, the ability to identify risk factors and develop prevention strategies has widespread health and fiscal importance. Seventy percent of ACL injuries occur in noncontact situations. The risk factors for non-contact ACL injuries fall into four distinct categories: environmental, anatomic, hormonal, and biomechanical. Early data on existing neuromuscular training programs suggest that enhancing body control may decrease ACL injuries in women. Further investigation is needed prior to instituting prevention programs related to the other risk factors.

Cutaneous metal sensitivity in patients with orthopaedic injuries.

BACKGROUND: Manufactures of orthopaedic fracture implants have turned to titanium in a pure form and an alloy during the past ten to fifteen years. Although primarily because of the biomechanical properties of this metal, concern for allergy to nickel and chromium ions in stainless steel was a factor in these decisions. OBJECTIVES: To document the incidence of baseline sensitivity to metal ions and the incidence of conversion to sensitivity to one of three ions in stainless steel in a population of trauma patients at a Level I trauma center. DESIGN: Prospective, consecutive patient series. SETTING: Level I trauma center. PATIENTS: Patients eighteen years of age and older with no history of metallic implants were recruited for this study between October 1995 and July 1997. Four hundred ninety-three patients had a Finn chamber device with chromium, nickel, and cobalt ions, which were read using a photographic scale on day three. Two hundred forty-two of these patients had placement of a second patch, at a mean interval of 187 days (range 45 to 589 days). INTERVENTION: Internal fixation of fracture or osteotomy with metal implant. MAIN OUTCOME MANAGEMENT: Cutaneous reactivity to metal ions. RESULTS: Prevalence of sensitivity to chromium was 0.2 percent, to nickel 1.3 percent, and to cobalt 1.8 percent. Rates for conversion from a negative to positive status were 2.7 percent for chromium, 3.8 percent for nickel, and 3.8 percent for cobalt. Rates for desensitization (i.e., converting from a positive to negative status) were 2.1 percent for nickel and 3.8 percent for cobalt. CONCLUSION: The prevalence of sensitivity to nickel, cobalt, and chromium is apparently low. Similarly, internal fixation devices composed of stainless steel appear to result in an equal incidence of conversion to metal ionic sensitivity and desensitization to metal ions. It is conceivable that cutaneous sensitivity is not representative of deep immune response.

Randomized prospective study of humeral shaft fracture fixation: intramedullary nails versus plates.

OBJECTIVES: To compare the clinical and radiographic results for locked intramedullary (IM) nails and plates used in the treatment of humeral diaphyseal fractures. DESIGN: Prospective randomization by sealed-envelope technique of eighty-four patients into two study groups: those treated by intramedullary nailing (IMN group; n = 38) and those treated by compression plating (PLT group; n = 46). SETTING: Patients admitted consecutively to a university-affiliated Level I trauma center. PATIENT/PARTICIPANTS: All skeletally mature patients admitted to Harborview Medical Center with acute humeral shaft fractures requiring surgical stabilization. Fractures of the diaphysis were defined as being at least three centimeters distal to the surgical neck and at least five centimeters proximal to the olecranon fossa. INTERVENTION: Treatment with locking antegrade intramedullary humeral nails (Russell-Taylor design [Smith and Nephew Richards]) or with 4.5-millimeter dynamic compression and limited contact dynamic compression plates (AO design [Synthes]). MAIN OUTCOME MEASUREMENTS: Clinical outcome measurements included fracture healing, radial nerve recovery, infection, and elbow and shoulder discomfort. Radiographic measurements included fracture alignment, time to healing, delayed union, and nonunion. RESULTS: Follow-up averaged thirteen months. Forty-two fractures (93 percent) in the PLT group were healed by sixteen weeks versus thirty-three fractures (87 percent) in the IMN group (p = 0.70). Shoulder pain and a decrement in shoulder range of motion (ROM) were significant associations with IMN (p = 0.007 for both variables) but not with PLT. A decrement in elbow ROM was significantly associated with PLT (p = 0.03), especially for fractures of the distal third of the diaphysis, whereas elbow pain was not (p = 0.123). The sum of other complications demonstrated nearly equal prevalence for both treatment groups. CONCLUSIONS: For patients requiring surgical treatment of a humeral shaft fracture, intramedullary nailing and compression plating both provide predictable methods for achieving fracture stabilization and ultimate healing.

Outcome validation of the AO/OTA fracture classification system.

OBJECTIVES: To determine whether a greater severity of injury as documented by the AO/OTA code would correlate with poor scores of impairment, functional performance, and self-reported health status. DESIGN: Prospective, functional outcome. SETTING: Three Level One Trauma Centers. PATIENTS/PARTICIPANTS: Two hundred patients with unilateral and isolated lower extremity fractures. MAIN OUTCOME MEASUREMENTS: Six- and twelve-month SIP, AMA impairment, and functional performance measures of self-selected walking speed, stair climbing, heel raises, rising from a chair, balance work. RESULTS: At six months post injury, overall impairment was significantly (p < 0.05) higher for patients with Type C versus Type B fractures. A significant difference was found among the A, B, C types and the ROM impairment rating at six months (p = 0.004). Using the Scheffe method, the significant difference was determined to be between the B- and C-type fractures. Overall functional performance scores at six months were shown to have significant (p = 0.01) variation using an ANOVA with the significant variation being between the B and C type. At twelve months, the overall functional performance was significant (p = 0.05). CONCLUSION: Patients with C-type fractures had significantly worse functional performance and impairment compared with patients with B-type fractures but were not significantly different from patients with A-type fractures. AO/OTA code may not be a good predictor of six- and twelve-month functional performance and impairment for patients with isolated unilateral lower extremity fractures.

Interobserver variation in the AO/OTA fracture classification system for pilon fractures: is there a problem?

OBJECTIVES: To evaluate the interobserver variation for the AO/OTA fracture classification system: region forty-three-pilon fractures. METHODS: One senior attending, two fellows (one trauma, one foot and ankle), one junior orthopaedic resident, and one experienced research coordinator independently classified eighty-four sets of radiographs. The evaluator was blinded as to treatment and functional outcome. The radiographs initially used to manage the patients were evaluated; no special radiographs or standardized radiographic techniques were used. The kappa statistic, Williams index, and SAV statistic were calculated. RESULTS: Using the SAV statistic to quantify rater agreement beyond that expected by chance alone, the average chance-adjusted agreement among the raters was 0.57 for fracture type, 0.43 for group, and 0.41 for subgroup. This is equivalent to moderate agreement (0.41 to 0.60). The kappa statistic was used to determine whether there was difficulty with any specific category of the AO type classification among raters for selecting fracture type (A, B, C). Kappa values were 0.49 for type A, 0.58 for type B, 0.57 for type C, all of which were considered adequate. CONCLUSION: These data are similar to others reported for interobserver agreement with the AO/OTA fracture classification and other classification systems. The issue of individual judgement in taking a continuous variable (fracture pattern) and compartmentalizing it into a dichotomous variable (fracture classification system) is highlighted by these data. Determination of fracture types alone (type A, B, or C) would seem to be sufficient for clinical research where fracture severity should be reported as a variable.

Treatment of type II, IIIA, and IIIB open fractures of the tibial shaft: a prospective comparison of unreamed interlocking intramedullary nails and half-pin external fixators.

OBJECTIVE: To compare unreamed intramedullary nailing (IMN) with external fixation (EF) in patients with Type II, IIIA, and IIIB open fractures of the tibial shaft. DESIGN: An inception cohort of consecutive patients with Type II, IIIA, and IIIB tibial fractures incurred between January 1988 and March 1993 were systematically allocated into one of two treatment groups. Patients were treated and followed with a prospectively designed protocol. PATIENTS AND SETTING: All patients were skeletally mature and had incurred a fracture of the tibial diaphysis within twenty-four hours of presentation to the tertiary care hospital, a Level I Trauma Center. One hundred seventy-four fractures in 168 patients were stabilized with either IMN (104) or half-pin EF (70). There were 132 men and thirty-six women, with an average age of thirty-three years (range, 14 to 77 years). INTERVENTION: Except for the selection of the fixation device, open fracture care was similar in the two treatment groups. All patients underwent emergent irrigation and debridement with concomitant skeletal stabilization. Cephalosporin antibiotics were administered perioperatively for twenty-four to forty-eight hours. No wounds were closed primarily. Delayed primary closure, skin grafting, and/or myoplasty were performed between three and ten days after injury. MAIN OUTCOME MEASURES: The main outcome measures were final fracture alignment, presence of infection or inflammation, hardware failure, time to union, and the number of operative procedures. RESULTS: The IMN group had significantly fewer incidences of malalignment than did the EF group [8 vs. 31 percent; p = 0.00005; confidence interval (CI) = 0.18, 0.76] and had significantly fewer subsequent procedures (mean of 1.7 vs. mean of 2.7 per fracture; p = 0.001; CI = 0.45, 1.59). IMN resulted in fewer infections/ inflammatory problems than did EF at the injury site (13 vs. 21 percent; p = 0.73; CI = -0.63, 0.45) and significantly fewer at surgical interfaces (i.e., pin sites, nail and interlocking screw insertion sites; 2 vs. 50 percent; p = 0.000; CI = 0.39, 0.60). No significant difference was found in the healing rates for the two implant groups. The more severe Gustilo injury types had longer healing times regardless of the type of fixation. CONCLUSIONS: Results suggest that unreamed interlocking intramedullary nails are more efficacious than half-pin external fixators, in particular with regard to maintenance of limb alignment. However, the severity of soft tissue injury rather than the choice of implant appears to be the predominant factor influencing rapidity of bone healing and rate of injury site infection.

Anterior cruciate ligament injury patterns among collegiate men and women.

OBJECTIVE: To determine potential patterns that cause males and females to tear the anterior cruciate ligament (ACL) while playing basketball or soccer. DESIGN AND SETTING: We reviewed data submitted to the National Collegiate Athletic Association Injury Surveillance System over the last 10 years, as well as profile data collected from collegiate certified athletic trainers. SUBJECTS: College athletes involved in basketball or soccer. MEASUREMENTS: Historical information was collected on those athletes involved in the National Collegiate Athletic Association Injury Surveillance System. Athletes involved in the profiling study underwent physical measurements related to flexibility, as well as a more detailed history relating to the ACL tear. RESULTS: College-age women involved in basketball or soccer tear their ACLs at significantly higher rates than college-age men involved in the same sports. No distinct physical or historical measurements could be attributed to this different rate of injury. CONCLUSIONS: Although the higher rate at which women compared with men tear their ACLs has persisted over the last 10 years, this increased incidence is not clearly attributable to any physical or historical measurements that were monitored.

Deleterious effect of smoking on healing of open tibia-shaft fractures.

We retrospectively reviewed a prospectively followed cohort of 105 patients with 110 open tibia fractures treated with external fixator or intramedullary nail to determine whether smoking affects fracture healing. Severe open tibia-shaft fractures treated at a tertiary-care medical center were included. Patients with type II, IIIA, or IIIB tibia fractures were eligible. Treatment for all patients was similar, except that they were randomized to receive external fixator or intramedullary nail. Time to fracture healing was the main outcome measurement. Smokers had a union rate of 84% (52/62), and nonsmokers had a union rate of 94% (45/48), P = .10. For smokers in one arm of the study, time to union was significantly longer (P = .01), and there were more complications (P = .04). Smoking decreased unions, slowed healing, and increased complications.

Comparison of interactive voice response and written self-administered patient surveys for clinical research.

This study compared the use of an interactive voice response (IVR) system with a written survey to collect data. Consecutive patients seen in an orthopedic clinic completed the Short Musculoskeletal Function Assessment (SMFA) by either IVR or written questionnaire and then were asked to complete the form again 3-7 days later using the opposite modality. Patient response rates were analyzed for differences between the self-administered IVR and written modes of administration. Three orthopedic clinics participated in the study. No significant differences between method of administration or individual differences in response per patient were found. Therefore, no significant differences in measurement are found when IVR is compared to the written SMFA.