The relationship between physical activity, structural deformity, and spinal mobility in adolescent idiopathic scoliosis patients.

PURPOSE: Adolescent idiopathic scoliosis (AIS) patients experience structural spinal deformity, but the impact of AIS on physical activity is not widely studied. Reports of physical activity levels between children with AIS and their peers are mixed. This study sought to characterize the relationship between spinal deformity, spinal range of motion, and self-reported physical activity in AIS patients. METHODS: Patients aged 11-21 completed self-reported measures of physical activity using the HSS Pedi-FABS and PROMIS Physical Activity questionnaires. Radiographic measures were obtained from standing biplanar radiographic imaging. Surface topographic (ST) imaging data was obtained using a whole-body ST scanning system. Hierarchical linear regression models analyzed the relationship between physical activity, ST, and radiographic deformity while controlling for age and BMI. RESULTS: 149 patients with AIS (mean age 14.5 ± 2.0 years, mean Cobb angle 39.7° ± 18.9°) were included. In the hierarchical regression predicting physical activity from Cobb angle, no factors were significant predictors of physical activity. When predicting physical activity from ST ROM measurements, age and BMI served as covariates. No covariates or ST ROM measurements were significant predictors of physical activity levels for either activity measure. CONCLUSIONS: Physical activity levels of patients with AIS were not predicted by levels of radiographic deformity or surface topographic range of motion. Although patients may experience severe structural deformity and range of motion limitations, these factors do not appear to be associated with decreased physical activity level utilizing validated patient activity questionnaires. LEVEL OF EVIDENCE: Level II.

Effect of increased serum 25(OH)D and calcium on structure and function of post-menopausal women: a pilot study.

The purpose was to determine if increasing serum 25(OH)D and calcium in postmenopausal women increased skeletal muscle size, strength, balance, and functional task performance while decreasing muscle fatigue. PCSA of the vastus lateralis increased and ascent of stairs time decreased after 6 months of increased serum 25(OH)D. PURPOSE: The Institute of Medicine recommends ≥ 20 ng/ml of serum 25-hydroxyvitamin D [25(OH)D] for bone and overall health. Serum 25(OH)D levels have been associated with physical performance, postural sway, and falls. The purpose of this study was to determine if increasing postmenopausal women's serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml improved skeletal muscle size, strength, balance, and functional performance while decreasing skeletal muscle fatigue. METHODS: Twenty-six post-menopausal women (60-85 years old) with baseline serum 25(OH)D levels between 20 and 30 ng/ml were recruited. Oral over-the-counter (OTC) vitamin D3 and calcium citrate were prescribed to increase subjects' serum 25(OH)D to levels between 40 and 50 ng/ml, serum calcium levels above 9.2 mg/dl, and PTH levels below 60 pg/ml, which were confirmed at 6 and 12 weeks. Outcome measures assessed at baseline and 6 months included muscle physiological cross-sectional area (PCSA), muscle strength, postural balance, time to perform functional tasks, and muscle fatigue. Repeated measures comparisons between baseline and follow-up were performed. RESULTS: Nineteen subjects completed the study. One individual could not afford the time commitment for the repeated measures. Three individuals did not take their vitamin D as recommended. Two subjects were lost to follow-up (lack of interest), and one did not achieve targeted serum 25(OH)D. Vastus lateralis PCSA increased (p = 0.007) and ascent of stair time decreased (p = 0.042) after 6 months of increasing serum 25(OH)D levels from 20-30 ng/ml to 40-50 ng/ml. Isometric strength was unchanged. Anterior-posterior center of pressure (COP) excursion and COP path length decreased (p < 0.1) albeit non-significantly, suggesting balance may improve from increased serum 25(OH)D and calcium citrate levels. CONCLUSIONS: Several measures of muscle structure and function were sensitive to elevated serum 25(OH)D and calcium levels indicating that further investigation of this phenomenon in post-menopausal women is warranted.

Osteoarthritis in England: Incidence Trends From National Health Service Hospital Episode Statistics.

OBJECTIVE: It is typical in epidemiological research of osteoarthritis (OA) to collect data for the hand, hip, and knee. However, little population-based data exist for this disease in the foot. Thus, we addressed patterns of OA for the foot compared with the hand, hip, and knee spanning 2000/2001 to 2017/2018 in England. METHODS: Secondary-care data from 3 143 928 patients with OA of the foot, hand, hip, and knee were derived from the National Health Service (NHS) Hospital Episode Statistics (HES) database. Distribution, population prevalence, and incidence of joint-specific OA were stratified by age and sex. RESULTS: OA incidence increased significantly at the foot [3.8% (95% confidence interval [CI] 3.0, 4.6)], hand [10.9% (10.1, 11.7)], hip [3.8% (2.9, 4.7)], and knee [2.9% (2.2, 3.6)] per year from 2000/2001 to 2017/2018. A higher proportion of women were diagnosed with OA, whereas greater incidence in men was estimated for the hand and hip. Foot OA presented comparable diagnosis numbers to the hand. More recently during 2012/2013 to 2017/2018, a significant rise in hip OA was estimated among younger adults, whereas knee OA decreased across all age groups. Incidence of OA in the foot and hand were particularly significant among the 75 or older age group, though bimodal age distributions were observed for both sites. CONCLUSION: The significant increase in secondary care records for OA in England underscores the importance of exploring possible causative factors and identifying groups most at risk. Further detailed data may be particularly important for the hip, which represents significant incidence among younger adults. Greater incidence of OA in the foot compared with the knee emphasizes the need for well-conducted epidemiological research in this area. Monitoring the performance of surgical outcomes at the population-level for this frequently affected yet understudied site could have substantial potential to reduce the socioeconomic burden it represents to the NHS.

Development and validation of a computational model of the knee joint for the evaluation of surgical treatments for osteoarthritis.

A three-dimensional (3D) knee joint computational model was developed and validated to predict knee joint contact forces and pressures for different degrees of malalignment. A 3D computational knee model was created from high-resolution radiological images to emulate passive sagittal rotation (full-extension to 65°-flexion) and weight acceptance. A cadaveric knee mounted on a six-degree-of-freedom robot was subjected to matching boundary and loading conditions. A ligament-tuning process minimised kinematic differences between the robotically loaded cadaver specimen and the finite element (FE) model. The model was validated by measured intra-articular force and pressure measurements. Percent full scale error between FE-predicted and in vitro-measured values in the medial and lateral compartments were 6.67% and 5.94%, respectively, for normalised peak pressure values, and 7.56% and 4.48%, respectively, for normalised force values. The knee model can accurately predict normalised intra-articular pressure and forces for different loading conditions and could be further developed for subject-specific surgical planning.

Factors associated with hallux valgus in a population-based study of older women and men: the MOBILIZE Boston Study.

OBJECTIVE: To examine potential risk factors for hallux valgus in community-dwelling elders. METHOD: Data from 600 MOBILIZE Boston Study participants (386 women and 214 men) were analyzed. Hallux valgus was defined as >15 degrees angular deviation of the hallux with respect to the first metatarsal bone toward the lesser toes. Associations of hallux valgus with age, body mass index (BMI), race, education, pes planus, foot pain, and in women, history of high heel shoe use, were assessed using sex-specific Poisson regression with robust variance estimation for risk ratios (RR) and 95% confidence intervals (CI). RESULTS: Hallux valgus was present in 58% of women and 25% of men. Higher BMI was inversely associated with presence of hallux valgus in women (P trend=0.001), with the strongest inverse association observed in those with BMI of 30.0 or more compared to those with normal BMI (RR=0.7, 95% CI: 0.5, 0.9). Women, who usually wore high-heeled shoes during ages 20-64 years compared to those who did not, had increased likelihood of hallux valgus (RR=1.2, 95% CI: 1.0, 1.5). Among men, those with BMI between 25.0 and 29.9 had increased likelihood of hallux valgus compared to those with normal BMI (RR=1.9, 95% CI: 1.0, 3.5). Men with pes planus were more likely to have hallux valgus (RR=2.1, 95% CI: 1.3, 3.3) compared to men without pes planus. CONCLUSION: In women, hallux valgus was associated with lower BMI and high heel use during ages 20-64, while in men, associations were observed with higher BMI and pes planus. Our results suggest that the etiologic mechanisms for hallux valgus may differ between men and women.

Lesser proximal interphalangeal joint arthrodesis: a retrospective analysis of the peg-in-hole and end-to-end procedures.

A retrospective study was performed to compare the prevalence of complications in peg-in-hole and end-to-end arthrodesis procedures. The authors reviewed 177 second, third, and fourth proximal interphalangeal joint fusions for the correction of hammer toe deformities in 85 patients from 1988 to 1998 at the Temple University School of Podiatric Medicine. The average age of the patients was 49 years. Sixteen percent (14) of the subjects were male and 84% were (71) female. Upon follow-up, the fourth digit was generally associated with a greater number of complications for the end-to-end and peg-in-hole procedures, with the second digit being the most common site of fusion. The prevalence of complications was evaluated using contingency table analysis and expressed as a percent of total complications (27%, the end-to-end group; 17%, the peg-in-hole group). A subset of complications deemed clinically relevant was also computed. Similarly, the prevalence of clinically relevant complications for the end-to-end (10%) and the peg-in-hole (9%) procedures was not statistically significant. Therefore, this study showed no statistically significant differences in the total or clinically relevant complications between end-to-end and the peg-in-hole arthrodesis procedures.

Acceleration of the calcaneus at heel strike in neutrally aligned and pes planus feet.

OBJECTIVE: The purpose of this research was twofold: (1) to study the impulsive acceleration of the calcaneus at heel strike in subjects with neutrally aligned (i.e., normal) feet and (2) to explore how the acceleration may differ in subjects with pes planus (i.e., flat) feet. The component of the acceleration vector aligned with the long axis of the tibia was quantified. DESIGN: Subjects with either foot type were instrumented and calcaneal acceleration was quantified during comfortable cadence locomotion. BACKGROUND: Aberrant peak acceleration has been associated with osteoarthritis. While tibial acceleration has been quantified, calcaneal acceleration has not. Additionally, foot morphology, or foot type, has demonstrated an effect on foot function and thus there may be differences in calcaneal acceleration between foot types. METHODS: Six subjects with neutrally aligned feet and six with pes planus feet were selected via a clinical exam. Accelerometers were attached to the posterior aspect of the medial surface of the calcanei bilaterally and 10 walking trials were collected.Results. The average baseline-to-peak acceleration for the neutrally aligned and pes planus feet was 4.79 g (SD, 2.14 g) and 5.24 g (SD, 3.28 g), respectively; the peak-to-peak acceleration was 5.03 g (SD, 2.74 g) and 6.75 g (SD, 3.89 g). There were no significant differences (P>0.05) between foot types. CONCLUSIONS: The calcaneal acceleration at heel strike for neutrally aligned and pes planus feet was not sensitive to foot type. RELEVANCE: Aberrant acceleration has been associated with the development of osteoarthritis [J. Biomech. 5 (3) (1972) 267; J. Biomech. 6 (1) (1973) 51; J. Biomech. 15 (7) (1982) 487]. Osteoarthritis at the subtalar joint, as well as the ankle and midtarsal joints, may be initiated and/or perpetuated by excessive calcaneal acceleration at heel strike.

Peg-in-hole, end-to-end, and V arthrodesis. A comparison of digital stabilization in fresh cadaveric specimens.

The proximal interphalangeal joint arthrodesis is frequently performed to correct hammer toe deformities. This study was conducted to compare the inherent stability of the three proximal interphalangeal joint arthrodeses--peg-in-hole, end-to-end, and V constructs--in the sagittal plane by means of load-to-failure testing of 30 fresh-frozen cadaveric specimens fixated with a 0.045 Kirschner wire. The peg-in-hole construct was associated with significantly higher peak loads at failure compared with the other two procedures. Furthermore, the peg-in-hole construct had significantly higher stiffness values as compared with the V procedure. This study thus provides evidence that the peg-in-hole procedure is the most biomechanically stable surgical construct for proximal interphalangeal joint fusions under sagittal plane loading.

The effect of foot orthoses on standing foot posture and gait of young children with Down syndrome.

The purpose of this study was to determine if foot orthoses (FOs) immediately affected gait of children with Down Syndrome (DS) and excessively pronated feet. Subjects were 3--6 years old; 16 with DS and 10 without disabilities. Gait of children with DS wearing sneakers was compared with and without FOs and compared to gait of children without disabilities. Ankle moment, walking speed during stance phase, sneaker prints, center of pressure, and transverse plane foot angles were collected and compared. In standing, heel eversion was reduced when the children wore FOs (p=0.000). During gait the transverse plane foot angle decreased indicating more internal rotation with FOs (p=0.000). Trial-to-trial variability of pronation-supination index (p=0.0001), foot length contact (p=0.0001), transverse plane foot angle (p=0.0003), and walking speed (p=0.0001) all decreased with FO use. Trial-to-trial variability of normalized peak ankle moment (p=0.0001), and of phase of peak ankle moment (p=0.0001) increased when the children wore FOs.

A case of peroneal neuropathy-induced footdrop. Correlated and compensatory lower-extremity function.

This article reports on the case of a man with peroneal neuropathy-induced footdrop who was seen at the authors' institution 3 years after open reduction and internal fixation of a proximal fibular fracture and a distal, spiral, oblique tibial fracture of the right leg. A comprehensive gait analysis was conducted. A significant footdrop in gait resulted in a "reverse check mark" center-of-pressure pattern, an increased transverse-plane rotation of the foot, and excessive knee and hip flexion in the sagittal plane. These objective findings documented significant dysfunction within the involved lower extremity; in addition, aberrant biomechanics were observed in structures other than the site of initial injury within both limbs.

Retrospective analysis of neurapraxia and axonotmesis injuries of select peripheral nerves of the foot and ankle and their conservative and surgical treatment (external neurolysis and neurectomy).

There is a paucity of scientific literature that has reviewed the conservative and surgical treatment efficacy for the management of injuries causing neurapraxia and axonotmesis. This retrospective study evaluates the clinical outcomes of certain treatments for these injuries. Twenty-seven patients fulfilled the inclusion/exclusion criteria for the study, and represented both genders and a wide variety of ages, weights, levels of education, and backgrounds. Surgical intervention resulted in a slightly better clinical outcome when compared to conservative therapies. Patients undergoing surgery for a single nerve problem improved more than those who underwent surgery when three or more nerves were involved. Failure was most often associated with: 1) multiple nerve injuries, 2) a previous history of psychopathology, and 3) application of conservative therapy without surgical intervention for single nerve injury.

Analysis of in vivo 3-D internal kinematics of the joints of the foot.

This paper describes a methodology for the analysis of three-dimensional (3-D) kinematics of live joints of the foot based on tomographic image data acquired via magnetic resonance (MR) imaging. A mechanical jig facilitates acquisition of MR images corresponding to different positions of the joint in a pronation-supination motion. The surfaces of the individual tarsal bones are constructed by segmenting the MR images. A mathematical description of the motion of the individual bones and of their relative motion is derived by computing the rigid transformation required to match the centroids and the principal axes of the surfaces. The mathematically described motion is animated via surface renditions of the bones. The kinematics of the bones are analyzed based on features extracted from the motion description and on how they vary with motion. Based on 17 joints that have been imaged, which includes an abnormal joint and the same joint after surgical correction, we conclude that this methodology offers a practical tool for measuring internal 3-D kinematics of joints in vivo and for characterizing and quantifying with specificity normal kinematics and their pathological deviations. Some of the 3-D kinematic animations generated using the methods of this paper for normal joints can be seen at: http:(/)/www.mipg.upenn.edu.

Bone grafting in foot and ankle surgery. A review of 300 cases.

Three hundred foot and ankle bone grafts were reviewed in three separate series of 100 consecutive grafts from two institutions. The series represent a period from 1977 to 1990 and demonstrate treatment patterns that varied over time and between institutions in indications, graft material, and perioperative management. Over 42% of the 300 grafts were for calcaneal osteotomies; most were Evans calcaneal osteotomies. Over 72% of the grafts were allogeneic bone-bank bone, which performed well in calcaneal osteotomies and for packing of defects. Upon review of the incidence of bone complications, no significant differences were observed between surgical procedures that used autogenous versus allogeneic grafts. However, four out of six failures of first metatarsal repair were with allogeneic bone. There was a significant difference in complication rates for the major indications for bone-graft surgery. Nonunions and arthrodeses resulted in higher complication rates than expected, whereas calcaneal osteotomies resulted in a lower complication rate than expected.

Gait analysis and bivalved serial casting of an athlete with shortened gastrocnemius muscles: a single case design.

Muscle tightness may predispose an athlete to injury. Stretching may help prevent injury by increasing joint passive range of motion and perhaps by increasing ankle range of motion during gait. The purpose of this study was to determine if bivalved serial casting and a positioning program would increase the total dynamic ankle range of motion without increasing the amount of compensatory foot pronation used during gait of an athlete with shortened gastrocnemius muscles. The subject was a 21-year-old male athlete. A three-dimensional camera-based kinematic system was used to collect functional dynamic ankle range of motion data. The Musgrave Footprint system was used to determine the relative amount of foot pronation (by measuring the pronation-supination index and dynamic foot angles). Data were collected for baseline, postintervention, and withdrawal phases. Data were then graphed and descriptively interpreted using means, standard deviations, trend, and level analyses. Following the treatment, the subjects showed an increase in mean total dynamic ankle range of motion without an increase in dynamic foot pronation. Eight weeks after treatment, the increase in mean total dynamic ankle range of motion was maintained and the pronation measurement did not change.

Tailor's bunion. Is fixation necessary?

Tailor's bunion or bunionette are terms that describe a pathologic enlargement occurring laterally on the fifth metatarsophalangeal joint. Regardless of the etiology that precipitates the deformity, the resulting abnormal protrusion of soft tissue or bone can result in pain for the patient. Symptoms can range from mild discomfort to severe, debilitating pain. The patient may present with pain dorsolaterally, laterally, or plantarly. The symptoms are mechanically induced, and are often associated with hyperkeratotic lesions and adventitious bursae. Patients complain most often that they cannot find comfortable shoes. The authors compare the effectiveness of fixated versus nonfixated distal osteotomies of the fifth metatarsal for the correction of tailor's bunion. This study shows that fixation can help control postoperative dorsal displacement of the fifth metatarsal capital fragment (p < 0.0001) and produce less shortening of the metatarsal resulting in fewer complications.

Tarsal tunnel syndrome. A retrospective study.

Many etiologies of tarsal tunnel syndrome exist, but it is difficult to determine the specific etiology for a patient. Surgical success rates vary in the literature from 44% to 100%. This retrospective study reviewed 40 patients with 45 data sets. Thirty-five patients (87.5%) in the study were female; 35 patients (87.5%) were caucasian. Thirty-two feet (71.1%) showed improvement following the tarsal tunnel surgery. The Tinel's sign parameter improvement was statistically significant. The differences in the subjective parameters of burning, radiating, and sharp sensations were statistically significant, while the differences in pins and needle sensation were nearly significant. The Takakura index and its constituent parameters were all statistically significant postoperatively with the exception of muscle atrophy, which did not have sufficient data for testing.

Foot type biomechanics. comparison of planus and rectus foot types.

The basic premise central to the diagnosis and treatment of most mechanogenic foot and ankle pathologies is that a given foot will display a characteristic function depending on the biomechanical alignment of the hindfoot and forefoot. However, the effects of foot type on an individual's ability to perform comfortable cadence locomotion have not been scientifically proven. Therefore, this study was conducted on 21 healthy, young subjects (10 subjects with planus foot type and 11 subjects with rectus foot type) to test whether different foot types yield distinguishable foot functions. New methods were developed to quantify biomechanical foot function during posture and comfortable cadence locomotion. The results of the study indicate that individuals with planus and rectus foot types show statistically significant differences in the biomechanical function of the foot.

Clinical applications of three-dimensional magnetic resonance image analysis.

A methodology for measuring the kinematic parameters of joints in vivo has been refined using the technique of computerized three-dimensional reconstruction from magnetic resonance images. A research protocol has been developed to establish a classification of normal and pathologic foot function that will have broad clinical application. Development of algorithms for a computer-directed program that can predict resultant kinematics and joint morphometry for a given osteotomy or osseous remodeling procedure will assist the surgeon in preoperative surgical planning.

Role of the plantar fascia in digital stabilization. A case report.

The plantar aponeurosis is a ligamentous structure that extends from the calcaneus to the proximal phalanges. Under tension, it functions to support the longitudinal arch, supinate the rearfoot, and stabilize the digits against the ground. The anatomy and biomechanics of the plantar fascia and plantar aponeurosis, particularly their role in digital stabilization, are reviewed. A case is presented showing a patient who developed hammer toes as a postoperative complication after having a portion of the plantar aponeurosis removed.