Valgus Inclination Research Articles

Supination resistance variations in foot and ankle musculoskeletal disorders: implications for diagnosis and customised interventions with wedged insoles

BackgroundSupination resistance is a clinical outcome that estimates the amount of external force required to supinate the foot. A greater supination resistance may indicate greater loads on structures responsible for generating internal supination moments across the subtalar joint during static and dynamic tasks. As such, greater supination resistance may be an expected finding in medial foot and ankle musculoskeletal disorders, such as plantar fasciopathy (PF) and posterior tibial tendon dysfunction (PTTD), whereas reduced supination resistance may be present in lateral ankle disorders, such as chronic ankle instability (CAI). However, no studies have yet investigated the changes in supination resistance across these foot and ankle musculoskeletal disorders. This study aimed to quantify supination resistance in individuals with PF, PTTD and CAI compared to healthy controls. Additionally, this study aimed to explore the changes in supination resistance following the simulation of varus and valgus wedges, which are commonly used interventions for these disorders.MethodsFourteen participants with PF, fourteen with PTTD, fourteen with CAI and fourteen healthy controls were recruited. Supination resistance was quantified on a level surface and on a 10-degree inclined surface with varus and valgus positions.ResultsSupination resistance was lower for the injured foot for CAI (p < 0.001) and greater for PTTD (p < 0.001) compared to the healthy foot. There was no significant between-foot difference observed for PF (p = 0.275) and controls (p = 0.970). In the injured foot, CAI exhibited lower supination resistance compared to controls (p < 0.001), PF (p = 0.012) and PTTD (p = 0.014). Regardless of the groups, supination resistance increased when tested on a surface with valgus inclination (p < 0.001) and decreased when tested on a surface with varus inclination (p < 0.001).ConclusionsVarus and valgus inclinations to the surface were effective in modifying supination resistance in PTTD and CAI, respectively. Supination resistance seemed unchanged in PF, and thus inclining the standing surface leads to greater between-feet asymmetries. This study also highlights the potential of wedged insoles as a mean to customise treatments and modify tissue stresses in these disorders. The findings contribute to the understanding of foot and ankle biomechanics and may aid in the development of more effective management and rehabilitation strategies.

Comparison of outcomes after different methods of fixation for extracapsular hip fractures: An observational study

ObjectiveOptimal management of intertrochanteric fractures using either sliding hip screws (SHS) or Intramedullary nail (IMN) fixation has long been disputed and the optimal length of a 'short nail' has yet to be clarified. Our aim was to investigate functional outcomes in patients who have undergone either sliding hip screw fixation or intramedullary fixation using varied lengths of nails to assess potential superiority. DesignWe retrospectively reviewed data from consecutive patients with trochanteric hip fractures between January 2010 - July 2019. Fracture fixation was performed with four different devices; SHS, 220mm and 175mm Targon PFT nails or 180mm Short Affixus Hip Fracture Nails. There was no significant difference in the patient demographics in each treatment group.Main outcome measures: Patients were followed up for 1 year post operatively to determine if there were differences in mobility and pain with the different fixation methods. ResultsThere was no significant difference in the overall complication rate between methods of fixation.Overall Intramedullary nail fixation resulted in an improved mean pain score compared to SHS (mean difference 0.25, 95% CI 0.11 - 0.39, p=0.0005). On sub-analysis this was only statistically significant in 220mm Targon nails (mean difference 0.35, CI 0.19-0.57, p=0.0010) and not for the other two nails.In addition, there was a significant difference in mobility score (mean difference 0.38, CI 0.12-0.63, p=0.0036). On sub-analysis this was only statistically significant favouring the for 220 mm Targon nail (mean difference 0.57, CI 0.27-0.87, p=0.0002). ConclusionWe advise caution in interpreting the results of studies between different nails and SHS, as not all nails appear to be the same. Design features of modern nails such as length, proximal diameter, the use of a compression screw, lag screw interface within the nail and valgus inclination may all play a role in functional outcomes.

Consensus for the Use of Weightbearing CT in the Assessment of Progressive Collapsing Foot Deformity.

There is evidence that the use of WEIGHTBEARING imaging aids in the assessment of progressive collapsing foot deformity (PCFD). The following WEIGHTBEARING conventional radiographs (CRs) are necessary in the assessment of PCFD patients: anteroposterior (AP) foot, AP or mortise ankle, and lateral foot. If available, a hindfoot alignment view is strongly recommended. If available, WEIGHTBEARING computed tomography (CT) is strongly recommended for surgical planning. When WEIGHTBEARING CT is obtained, important findings to be assessed are sinus tarsi impingement, subfibular impingement, increased valgus inclination of the posterior facet of the subtalar joint, and subluxation of the subtalar joint at the posterior and/or middle facet. Level V, consensus, expert opinion.

Effects of Total Hip Arthroplasty on Axial Alignment of the Lower Limb in Patients with Unilateral Developmental Hip Dysplasia (Crowe type IV)

BackgroundThe aim of this study was to evaluate the influence of total hip arthroplasty on axial alignment of the lower limb in adults with unilateral developmental hip dysplasia (Crowe type IV). MethodsWe retrospectively reviewed medical records of 50 adults who underwent total hip arthroplasty, in which the acetabular cup was placed in the anatomical position. The following parameters were measured before surgery, immediately after surgery, and two years later: mechanical axis deviation (MAD), tibiofemoral angle (TFA), femoral offset, hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (LDFA), mechanical medial proximal tibial angle, height of medial femoral condyle, height of lateral femoral condyle, and leg lengthening. Length of the resected femoral segment was also recorded from medical records. ResultsPreoperative MAD, TFA, HKA, and LDFA of the ipsilateral lower limb showed significant valgus deformity. MAD of the ipsilateral lower limb and valgus inclination were significantly smaller immediately after surgery than before, while TFA, HKA, femoral offset, and LDFA were significantly larger (P < 0.05). These parameters did not differ significantly between immediately after surgery and two years later (P > 0.05). Ipsilateral extremities were extended by a mean of 2.54 cm (range, 0 to 5.35 cm). The mean length of the femoral resected segment was 3.56 cm (range, 2.03 to 5.74 cm). The contralateral lower limb showed marginally smaller MAD and medial proximal tibial angle after surgery than before, but larger LDFA, TAF, and HKA. ConclusionsIn patients with developmental hip dysplasia who underwent total hip arthroplasty with placement of the acetabular component at the level of the anatomic hip center, axial alignment of the ipsilateral lower limb was immediately altered, and valgus inclination was significantly reduced. The procedure only slightly altered the axial alignment of the contralateral lower limb.

Surgical correction of distal tibia posttraumatic deflection

Objective – to study the issues related to diagnostics and treatment of pilon fracture of the tibial epiphysis and individual approach to surgical correction of posttraumatic deformations of the distal tibia.Material and methods. The treatment results of 49 patients who had suffered pilon fractures throughout 1–2 years after treatment completion were studied in the clinic of Traumatology and Orthopedic on the basis of “ZSMKH №9”. According to the AO classification patients had the following types of fractures: 43A – 7 patients, 43B – 14 and43C – 28. The X-ray measurements characterizing the geometric shape of articular surfaces were measured. The mathematical finite element method of computer modeling was used for the study of bone and cartilaginous tissues stress distribution pattern in the ankle joint in its normal condition and in case of post-traumatic deflections.Results. The basic pathological symptom in patients with pilon fractures of distal tibia is joint function limitation, which spreads to the sector of dorsal extension, regardless of the pilon fracture type. The joint continues to function, however movement amplitude is decreased. The most unfavorable change of distal tibia shape is valgus inclination of articular surface. This configuration change of tibial articular end requires repeated surgical correction.Conclusions. The main task of the distal tibial epiphysis surgical correction is the weight-bearing function and axial relationships restoration and pain management. It can be concluded that selective approach to posttraumatic deformations of the distal tibia surgical correction is essential. The main indications for surgical correction are pseudarthrosis, deviations in the frontal plane of more than 10 degrees, severe joint arthrosis accompanied by pain syndrome for more than a year.

The adaptive change of patellofemoral joint after arthroscopic discoid lateral meniscus plasty: An observational study.

The purpose of this study was to investigate the patellofemoral joint adaptive changes after discoid lateral meniscus (DLM) plasty.Forty-one patients with unilateral complete type DLM tears were included in this study. Demographic variables, including gender, age, body mass index (BMI), injury to operation interval, type of injury, and follow-up time, were recorded. The evolution of physical examination, imaging index, and functional score were analyzed by Chi-squared test, Wilcoxon signed ranks test, and Friedman test. Mann–Whitney test was used to analyze the difference at different time points between group PFI > 1.6 and PFI < 1.6.After the patients received arthroscopic DLM plasty, the positive rate of Patella grinding test increased from 19.5% to 29.3%, and it showed significant increased at last follow-up time point (48.8%) (P = .005). Mechanical axis deviation (MAD) significant decreased from −0.7 ± 2.1 mm to −9.4 ± 3.2 mm (P < .001). Lateral patellofemoral angle (LPFA) and lateral shift distance (LSD), respectively, decreased from 11.9 ± 5.8° and 1.0 ± 4.0 mm to 7.2 ± 4.5° and −0.5 ± 3.3 mm (P < .001). Patellofemoral index (PFI) increased from 1.7 ± 0.3 to 1.9 ± 0.4 (P < .001). Kujala score and Lysholm score, respectively, increased from 65.9 ± 10.0 and 85.2 ± 6.4 mm to 61.8 ± 10.2 and 89.5 ± 5.0 (P < .001). Only LSD in group > 1.6 were significant lower than those in group < 1.6 (>1.6: −1.5 ± 2.8, −1.6 ± 2.7, −1.5 ± 2.6; <1.6: 0.8 ± 3.4, 0.4 ± 3.6, 0.6 ± 2.8. P = .010,.038,.011) at the 3 postoperative follow-up time points.After arthroscopic plasty for complete type DLM which decreased the thickness and width of the residual meniscus, in turn causing the varus deformity significantly decreased or a valgus inclination developed. Moreover, the consequent changes of patellofemoral joint caused a certain amount of patellar tilt and patellar dislocation, might aggravated the symptomatic anterolateral knee pain or the lateral patellar compression syndrome.

Midterm results of surface replacement of the shoulder

PurposeThis study was undertaken to determine the midterm results of resurfacing hemiarthroplasty of the shoulder, evaluate the inclination of prosthesis and correlate the effect of valgus or varus positioning on clinical outcomes. MethodsBetween 2007 and 2014, fifty-seven humeral head surface replacements were performed in our hospital for the osteoarthritis of shoulder. One patient expired and 6 shoulders were lost to follow-up. Forty-seven patients with 3 patients having bilateral humeral head replacements, were assessed thoroughly at the mean period of 4.4+2.3years (Range 2–9 years). All fifty shoulders were evaluated using the VAS, ASES and Constant and Murley score. ResultsHumeral head surface replacement produced satisfactory results in 96% of the patients at a mean follow-up of 4.4 years. We found that the difference in mean postoperative ASES, Constant and VAS score in normal and valgus inclination angle shoulders was not significant whereas the difference in normal and varus inclination angle shoulders was significant. Three patients had severe pain with VAS score (range 0 to 10) of 7, 5 and 4 postoperatively though in all 3 patient’s inclination angle was normal. No revision surgery was performed till recent follow-up. ConclusionsIn conclusion mid-term outcomes of the uncemented Global C.A.P. resurfacing prosthesis are promising. Inclination of the implant has effect on functional outcome of patients.

The Valgus Inclination of the Tibial Component Increases the Risk of Medial Tibial Condylar Fractures in Unicompartmental Knee Arthroplasty

BackgroundMedial tibial condylar fractures (MTCFs) are a rare but serious complication after unicompartmental knee arthroplasty. Although some surgical pitfalls have been reported for MTCFs, it is not clear whether the varus/valgus tibial inclination contributes to the risk of MTCFs. MethodsWe constructed a 3-dimensional finite elemental method model of the tibia with a medial component and assessed stress concentrations by changing the inclination from 6° varus to 6° valgus. Subsequently, we repeated the same procedure adding extended sagittal bone cuts of 2° and 10° in the posterior tibial cortex. Furthermore, we calculated the bone volume that supported the tibial component, which is considered to affect stress distribution in the medial tibial condyle. ResultsStress concentrations were observed on the medial tibial metaphyseal cortices and on the anterior and posterior tibial cortices in the corner of cut surfaces in all models; moreover, the maximum principal stresses on the posterior cortex were larger than those on the anterior cortex. The extended sagittal bone cuts in the posterior tibial cortex increased the stresses further at these 3 sites. In the models with a 10° extended sagittal bone cut, the maximum principal stress on the posterior cortex increased as the tibial inclination changed from 6° varus to 6° valgus. The bone volume decreased as the inclination changed from varus to valgus. ConclusionIn this finite element method, the risk of MTCFs increases with increasing valgus inclination of the tibial component and with increased extension of the sagittal cut in the posterior tibial cortex.

Finite Element Analysis of Mobile-bearing Unicompartmental Knee Arthroplasty

Background:Controversies about the rational positioning of the tibial component in unicompartmental knee arthroplasty (UKA) still exist. Previous finite element (FE) studies were rare, and the results varied. This FE study aimed to analyze the influence of the tibial component coronal alignment on knee biomechanics in mobile-bearing UKA and find a ration range of inclination angles.Methods:A three-dimensional FE model of the intact knee was constructed from image data of one normal subject. A 1000 N compressive load was applied to the intact knee model for validating. Then a set of eleven UKA FE models was developed with the coronal inclination angles of the tibial tray ranging from 10° valgus to 10° varus. Tibial bone stresses and strains, contact pressures and load distribution in all UKA models were calculated and analyzed under the unified loading and boundary conditions.Results:Load distribution, contact pressures, and contact areas in intact knee model were validated. In UKA models, von Mises stress and compressive strain at proximal medial cortical bone increased significantly as the tibial tray was in valgus inclination >4°, which may increase the risk of residual pain. Compressive strains at tibial keel slot were above the high threshold with varus inclination >4°, which may result in greater risk of component migration. Tibial bone resection corner acted as a strain-raiser regardless of the inclination angles. Compressive strains at the resected surface slightly changed with the varying inclinations and were not supposed to induce bone resorption and component loosening. Contact pressures and load percentage in lateral compartment increased with the more varus inclination, which may lead to osteoarthritis progression.Conclusions:Static knee biomechanics after UKA can be greatly affected by tibial component coronal alignment. A range from 4° valgus to 4° varus inclination of tibial component can be recommended in mobile-bearing UKA.

Impact of Ulnar Collateral Ligament Tear on Posteromedial Elbow Biomechanics.

Ulnar collateral ligament insufficiency has been shown to result in changes in contact pressure and contact area in the posteromedial elbow. This study used new digital technology to assess the effect of a complete ulnar collateral ligament tear on ulnohumeral contact area, contact pressure, and valgus laxity throughout the throwing motion. Nine elbow cadaveric specimens were tested at 90° and 30° of elbow flexion to simulate the late cocking/early acceleration and deceleration phases of throwing, respectively. A digital sensor was placed in the posteromedial elbow. Each specimen was tested with valgus torque of 2.5 Nm with the anterior band of the ulnar collateral ligament intact and transected. A camera-based motion analysis system was used to measure valgus inclination of the forearm with the applied torque. At 90° of elbow flexion, mean contact area decreased significantly (107.9 mm(2) intact vs 84.9 mm(2) transected, P=.05) and average maximum contact pressure increased significantly (457.6 kPa intact vs 548.6 kPa transected, P<.001). At 30° of elbow flexion, mean contact area decreased significantly (83.9 mm(2) intact vs 65.8 mm(2) transected, P=.01) and average maximum contact pressure increased nonsignificantly (365.9 kPa intact vs 450.7 kPa transected, P=.08). Valgus laxity increased significantly at elbow flexion of 90° (1.1° intact vs 3.3° transected, P=.01) and 30° (1.0° intact vs 1.7° transected, P=.05). Ulnar collateral ligament insufficiency was associated with significant changes in contact area, contact pressure, and valgus laxity during both relative flexion (late cocking/early acceleration phase) and relative extension (deceleration phase) moments during the throwing motion arc.

Short-term effects of discoid lateral meniscectomy on the axial alignment of the lower limb in adolescents.

A discoid lateral meniscus in the knee is more common in Asian populations. The aim of this study was to evaluate the influence of arthroscopic meniscectomy of the discoid lateral meniscus on the axial alignment of the lower limb in adolescents (younger than twenty years of age). We retrospectively reviewed the data from 298 adolescent patients (younger than twenty years of age) who underwent arthroscopic treatment in our center from 2004 to 2013. Patients were divided into three groups according to the meniscus type: torn discoid lateral meniscus (Group A), torn nondiscoid lateral meniscus (Group B), and nondiscoid lateral meniscus without a tear (Group C). The tibiofemoral angle (TFA) and mechanical axis deviation (MAD) of both lower limbs were examined on standing anteroposterior radiographs before and after arthroscopy. The preoperative TFA and MAD of the ipsilateral lower limbs demonstrated significantly more varus in Group A than in Group B (p < 0.001) or Group C (p < 0.001) after we controlled for the contralateral lower limbs as a covariate factor. Moreover, the TFA and MAD of the ipsilateral knees were significantly reduced (indicating a reduction in varus inclination) postoperatively, as compared with preoperatively, in Group A (p < 0.001) and Group B (p < 0.001), with no difference between the preoperative and postoperative values in Group C (p > 0.01), after we controlled for the contralateral lower limb as the covariate factor. Additionally, the reductions in the TFA and MAD (varus inclination) in Group A were significantly greater than those observed in Group B (p < 0.001). The axial alignment of the lower limb in adolescents (younger than twenty years of age) with a torn discoid lateral meniscus was altered immediately after arthroscopic meniscectomy: the varus deformity was significantly reduced, and a valgus inclination developed in some of these patients. The valgus inclination was more pronounced in the patients with a torn discoid lateral meniscus compared with those with a torn nondiscoid lateral meniscus.

Congenital posteromedial bowing of the tibia: a retrospective analysis of growth abnormalities in the leg

We studied case records and radiographs of 20 children with congenital posteromedial bowing of the tibia (CPMBT) retrospectively to determine the pattern of correction of the bowing, the associated growth abnormalities of the tibia and fibula, and the role of surgical intervention in CPMBT. The magnitude of diaphyseal bowing in two planes and the physeal inclination were measured. Abnormalities of ossification of the distal tibial epiphysis and inclination of the distal articular surface if present were noted and shortening of the tibia was recorded. The rate of resolution of deformity was noted from sequential radiographs and expressed as percentage reduction per month of follow-up. At initial presentation the magnitude of deformity varied; the most severe posterior diaphyseal bow was 70 degrees whereas the most severe medial diaphyseal bow was 64 degrees. Two distinct mechanisms seem to be responsible for resolution of the deformity in CPMBT; one involves physeal realignment and the other involves diaphyseal remodeling. In the first year of life, rapid resolution of angulation was noted; the rate of resolution reduced significantly thereafter. In a proportion of children with CPMBT residual deformity may persist till over 4 years of age. Physeal realignment occurred at a faster rate than diaphyseal remodeling. The degree of shortening was related to the severity of bowing and shortening as great as 40% was noted in a patient. Wedging of the distal tibial epiphysis and fibular hypoplasia with valgus inclination of the distal tibial articular surface occur in some children with CPMBT. Eccentric ossification of the distal tibial epiphysis in early childhood may be a predictor of wedging of the distal tibial epiphysis later on. We recommend all the children with CPMBT to be followed up periodically till skeletal maturity, to identify cases with residual bowing, ankle deformity, muscle weakness, and limb length inequality as active surgical intervention may be needed to correct these problems.

Correlation of Compensatory Alignment of the Subtalar Joint to the Progression of Primary Osteoarthritis of the Ankle

The etiology of primary osteoarthritis of the ankle is not well understood. The varus deformity of the ankle and the compensatory function of the subtalar joint are expected to be important factors in the progression of osteoarthritis. The purpose of this study was to document joint inclination at the various stages and to try to deduce the mechanism of primary, varus osteoarthritis of the ankle. Weightbearing ankle anteroposterior (AP) views, lateral views and subtalar views were taken for 133 ankles in 80 patients (OA group) and 62 ankles in 50 subjects (control group). The OA group was divided into 5 radiographic stages. The inclination of the articular surface of the tibial plafond, the talar dome and the posterior facet of the calcaneus were measured from the radiographs. The inclination of the subtalar joint against the ankle was also calculated. At each stage, each value of the OA group was compared with the control group. The varus inclination of the articular surface of the tibial plafond progressed by stages; however, anterior opening was not significant at all stages. The valgus inclination of the subtalar joint progressed until the intermediate stage and converted to varus position at the later stage. CONCLUSION The compensatory function of the subtalar joint was most pronounced at the intermediate ankle arthritis stage.

Three-dimensional finite element analysis of unicompartmental knee arthroplasty––the influence of tibial component inclination

Aseptic loosening and failure of a tibial component are recognized problems in unicompartmental knee arthroplasty (UKA). Excessive stress on the supporting cancellous bone is thought to contribute to the loosening and failure. Of factors that could influence supporting cancellous bone stresses, we focused on the inclination of a unicompartmental tibial component by analyzing the effect of coronal plane and sagittal plane inclination. Detailed geometrically accurate, three-dimensional finite element models were constructed from computed tomography (CT) data of a typical adult male proximal tibia. The material properties for the models were obtained directly from the CT data to simulate the inhomogeneous distribution of cancellous bone properties. Placing the component in slight valgus inclination in the coronal plane reduced the cancellous bone stresses. Posterior inclination in the sagittal plane caused a moderate increase in the stresses. Our results suggest that slight valgus inclination of a UKA tibial component may be preferable to varus or square inclination in the coronal plane. An excessive posterior slope of a tibial component should be avoided.

Morphology of the knee in adult patients with neglected developmental dysplasia of the hip.

Although there have been numerous studies on the treatment of developmental dysplasia of the hip, few have focused on its natural history into adulthood. We observed valgus deformity of the knee in a group of adult patients with developmental dysplasia of the hip. To the best of our knowledge, there has been no detailed study of that condition. The purpose of this study was to investigate structural changes of the knee in patients with neglected developmental dysplasia of the hip. Thirty-four adult patients with neglected developmental dysplasia of the hip and ten healthy adults were evaluated. The lower extremities were grouped according to the severity of the dysplasia. The morphology of the knees was evaluated with radiographic measurements, and the groups were compared. Compared with the control group, the patients with severe developmental dysplasia of the hip had significant valgus deformity of the knee. This finding was associated with an increased vertical dimension of the medial femoral condyle, which led to a valgus inclination of the distal femoral articular surface. Although the femoral sulcus was shallower in the patients with developmental dysplasia of the hip, patellofemoral congruency was not deranged. The pathologic condition of the hip joint in patients with developmental dysplasia of the hip results in developmental changes in the osseous anatomy of the knee joint, with the development of a valgus deformity of the lower extremity. If any surgical intervention is planned in a patient with developmental dysplasia of the hip, the whole lower extremity should be carefully analyzed, with special attention to the morphology of the knee, to avoid creating problems of malalignment.

The effects of tibial component inclination on bone stress after unicompartmental knee arthroplasty

Unlike the case with total knee arthroplasty, the femorotibial angle (FTA) after unicompartmental knee arthroplasty (UKA) does not directly depend on the inclination of the tibial component when the height of the joint line is maintained. This study analyzed the effects of the inclination of the tibial component in the coronal plane on the contact pressure of the implant–bone surface and the stresses on the proximal tibia. A two-dimensional, coronal plane model of the proximal tibia was subjected to finite-element analysis. Sixteen patterns of finite-element models of equal FTA were developed in which the inclination of tibial components ranged from 5° valgus to 10° varus in increments of 1°. Stress concentration at the proximal medial diaphyseal cortex gradually increased as the inclination changed from valgus to varus. Maximum contact pressure on the metal–bone interface similarly changed and shifted from the lateral edge to the medial edge of the implant as the inclination changed to varus. It was found that even without changing FTA, the inclination of the tibial component might affect stress concentration and contact pressure in the proximal tibia after UKA. The results suggested that slight valgus inclination of the tibial component might be preferable to varus and even to 0° (square) inclination so far as the stress distribution is concerned.

Morphologic changes of the ankle in children as assessed by radiography and arthrography

Chronological changes in the morphology of the ankle, a joint that consists primarily of chondral components in children, were investigated by arthrography and plain radiography. Arthrography was performed in 57 ankles of 40 patients with normal ankles (aged from 2 months to 3 years, 4 months; mean, 1 year, 7 months), and plain radiography was performed on 183 joints of 126 patients with normal ankles (aged from 3 years, 6 months to 14 years, 5 months (mean, 7 years, 8 months). The angle of the distal tibial joint surface was then measured on each radiograph. Despite being evident at birth, valgus inclination in the ankle rapidly changed during the first and second years of life. Thereafter, change continued gradually and spontaneously, and the ankles were in the neutral position by 3 years of age. However, the morphology of the ankles did not change much after that time. Normal ankles show valgus inclination at birth, but this configuration is changed naturally over time, and the ankles are in the neutral or slightly varus position by the age of bone maturity.

Discoid lateral menisci in older patients

Twenty-three knees of 21 patients over 40 years of age with discoid lateral menisci were examined by radiography. The mean age of the patients was 59.7 years (range: 40-78 years). No patient had symptoms before the age of 40 and only 12 knees gave symptoms from the lateral compartment, although tears of a discoid lateral meniscus were diagnosed by arthrography in 21 of the 23 knees. Varus inclination occurred more frequently than valgus inclination. Subchondral bone sclerosis was more common in the medial compartment. However, high incidences of marginal osteophytes in the lateral compartment and morphological anomalies (cupping or flattening) of the lateral tibial plateau were revealed by radiography.

Motion and laxity of the capitellocondylar total elbow prosthesis.

The motion and laxity of the capitellocondylar unconstrained total elbow prosthesis were assessed, with use of an electromagnetic tracking device and stimulated muscle-loading, after implantation in seventeen cadaveric elbows. The axis of motion of the elbows with the capitellocondylar implants averaged 2.1 +/- 2.3 degrees more varus angulation than that of the intact elbows. This difference may be attributed to the design of the implant, as the 5-degree-valgus humeral component used in this study has a smaller valgus inclination than the articular surface of the distal aspect of the humerus. Although the maximum valgus-varus laxity of the capitellocondylar elbow prostheses was, on the average, 4.3 +/- 2.4 degrees greater than normal (with simulated muscle-loading), the data must be interpreted in light of the fact that this in vitro study did not allow for soft-tissue healing. The prosthetic components tracked well, and there were no dislocations or malarticulations provided that appropriate soft-tissue tensioning and positioning of the components had been achieved at the time of implantation. Sectioning of either the medial or the lateral collateral ligament resulted in gross instability of the joint after capitellocondylar arthroplasty. The ulnar attachment of the medial collateral ligament was found to be vulnerable to injury during the positioning of the ulnar component of this implant.

Foot-Ground Pressure Pattern of Flexible Flatfoot in Children, With and Without Correction of Calcaneovalgus

The footprint-measuring instrument was used to establish foot-ground pressure pattern of flexible flatfeet in male and female children, aged four to six years. Standing at ease, the children exerted most of their ground pressure by the posterior weight-bearing area (WBA). The rest was distributed between the middle and anterior WBAs, with the middle area usually exerting about 17%, and in extreme cases, as much as 30% of the total foot-ground pressure. Correcting valgus inclination of the calcaneus into neutral by inserting a leather wedge under the medial portion of the heel restored the longitudinal arch and the normal distribution of the foot-ground pressure of the standing child. The middle WBA exerted only 6% of the total pressure. This measuring system can differentiate between a normal foot, a flexible flatfoot, and a rigid flatfoot. It also can measure the exact amount of abnormal pressure being exerted by the middle WBA.