Relevance of the popliteal angle to hamstring length in cerebral palsy crouch gait

The popliteal angle is a widely used clinical means of assessing hamstring length in cerebral palsy patients. The relevance of the popliteal angle as a measure of hamstring length was assessed in this prospective study. Sixteen patients with cerebral palsy with crouch gait had their conventional and modified popliteal angles measured by nine observers on two separate occasions. With use of the conventional and modified forms of the test, 74 and 70%, respectively, of the observed variability was inter-and intraobserver related. The range of SDs for each observer using the conventional test was 7.1-13.6 degrees (average 10.9 degrees ), and with use of the modified form of the test, the range was 6.3-4.2 degrees (average 10.5 degrees ). The maximum hamstring length of each subject during gait was determined by three-dimensional modelling of their lower limbs. The modified popliteal angle measurements of the most repeatable observer demonstrated an inverse relationship between modified popliteal angle and maximum hamstring length (p < 0.01) and muscle excursion (p < 0.01). Only 10 of 32 limbs had short medial hamstrings.

Motor functions in non-ambulatory children with spastic diplegia and periventricular leukomalacia

The course of acquisition of various gross motor skills and changes in their patterns with advancing age, in addition to joint contracture, hand function, and mental ability, were investigated in 20 non-ambulatory children with spastic diplegia and periventricular leukomalacia. Among the diplegic children studied, those with lower locomotive ability also had lower hand function, lower mental ability and slower acquisition of gross motor skills. All subjects could roll by 24 months of age. Fourteen patients could creep by 18 months of age, and the remaining six by 30 months. Crawling was observed in only five patients with mild locomotive disability as a final locomotive pattern on the floor. Among ten patients with mild locomotive disability, three could sit by 2 years of age, six by 3 years, and one by 4 years. Among ten patients with severe disability, two, two, four and two children could sit at the ages of 2, 3, 4 and 5 years, respectively. Twelve patients could walk with support at between 2 and 5 years of age. Delay in acquisition of creeping or sitting differed somewhat among subjects with similar final locomotive disability. The majority of subjects with severe locomotive disability developed contracture of the hips and knees. Only two patients with mild disability had contracture of the ankles.

Changes in dorsal horn neuronal responses in an experimental wrist contracture model

Joint contracture, a major complication after casting, usually makes the therapeutic outcome worse by causing a limited range of motion and related pain. We developed rat models of wrist contracture with fracture of the radius (group A) and wrist contracture without fracture (group B), and investigated whether contracture and fracture changed the characteristics of cervical dorsal horn neuronal responses and the behavior of the animals. After 4 weeks of immobilization, both groups showed wrist contracture and disuse tendencies in the treated forelimb. In an electrophysiological study, the responses of 403 cervical dorsal horn neurons to mechanical stimuli were examined. In normal (control) animals, the neurons had the following distribution: 63% were low-threshold (LT); 15% were high-threshold (HT); and 22% were wide-dynamic-range (WDR). In group A, the distribution of the neurons changed to 51% LT, 16% HT, and 33% WDR. Similar changes were observed for group B. Responses during wrist movement were also examined. Forty-one percent of cells in the control group were responsive to the movements, whereas the number of neurons responding to motion stimulus in both groups A and B was increased, to 77%. The changed population of WDR and LT neurons responding to wrist movement suggests that the characteristics of dorsal horn neurons may undergo plastic changes after contracture.

Musculoskeletal deformities in Behr syndrome

SUMMARY

Seventeen children with Behr syndrome were investigated, focusing on the musculoskeletal deformities and long-term outcome. Behr syndrome is characterized by optic atrophy beginning in early childhood associated with ataxia, spasticity, mental retardation, and posterior column sensory loss. The ataxia, spasticity, and muscle contractures, mainly of the hip adductors, hamstrings, and soleus, are progressive and become more prominent in the second decade. In 70% of the patients, contractures developed in the lower limbs, requiring surgery mainly for the Achilles tendon, hamstrings, and adductor longus. At last follow-up at an average age of 21.7 years (range, 8-31 years), 13 of the patients are housebound walkers, 2 are nonfunctional walkers, and 2 are nonwalkers.

[Correction of cervical contractures after burns with pedicled latissimus dorsi musculocutaneous flaps]

In selected cases of cervical retractions after burns, the authors show that pedicled latissimus dorsi musculocutaneous flaps may be of great help if properly performed. The main advantages of this method are its simplicity and the lack of need for a postoperative cervical splint.

[Supracondylar femoral extension osteotomy for knee flexion contracture correction in poliomyelitic conditions]

PURPOSE OF THE STUDY

Knee flexion contracture due to quadriceps paralysis is a major handicap in poliomyelitis patients. The patient has to stabilize the knee with the ipsilateral hand to achieve weight bearing and the deformed knee precludes use of orthopedic devices. Extension can be achieved with supracondylar femoral osteotomy if the knee flexion contracture is less than 30 degrees. We assessed functional and anatomic outcome.

MATERIAL AND METHODS

We reviewed the files of 87 patients who had undergone 93 supracondylar femoral osteotomies for knee flexion contracture (6 bilateral cases); mean age was 18 years and mean flexion was 25 degrees. The surgical correction was achieved by diaphyseal metaphyseal impaction with resection of an anterior wedge and preservation of the posterior component of the articulation. If some gluteus maximus activity was retained and the tibiotarsal joint was in a slightly equine position, weight bearing in a stable locked position became an automatic postural event even in case of total paralysis of the quadriceps. Osteotomy was not possible if the contracture flexion was greater than 30 degrees due to excessive tension on the vaculonervous bundles. The procedure was equally impossible in children under 12 years of age due to the risk of recurrence subsequent to migration and callus remodeling with bone growth.

RESULTS

Complete extension of the knee was achieved peroperatively in all cases. The most serious complications were three cases of septic arthritis that led to an irreducible stiff knee. In addition, we had two cases of transient paralysis of the common fibular nerve that recovered spontaneously. Bone fusion was achieved in all cases within 30 days. Recurrent flexion contracture was observed in 5 cases and required a revision using the same procedure in 3 or them. Postoperatively, the amplitude gained in knee extension corresponded to the amplitude lost for flexion. Sixty-three patients were able to walk independently without manual stabilization and a knee extension orthesis could be installed for 19 others. Three patients were still unable to walk despite the correction of the knee flexion contracture due to failure of poorly accepted orthopedic devices.

DISCUSSION

Several conservative methods (physiotherapy, manipulations, successive corrective casts) and surgical procedures (release of posterior soft tissues, Ilizarov technique) have been proposed for the correction of paralytic knee flexion contracture. Supracondylar femoral osteotomy for extension can be useful after the end of growth if the flexion contracture remains below 30 degrees. The procedure is simple and morbidity is relatively low compared with the regularly successful results. When the flexion contracture exceeds 30 degrees, the supracondylar osteotomy cannot be employed due to the risk of stretching the vasculonervous bundles and due to the instability and disorganization of the lower femur. Progressive correction can be proposed for these patients: regular monitoring of the neurological and vascular situation is required. Functional improvement is considerable after correction of knee flexion contracture. The patients can walk more easily, no longer need to stabilize their knee with their hand, and can benefit from orthopedic devises due to the more favorable biomechanical conditions.

Bone growth increases the knee flexion contracture angle: A study using rats

OBJECTIVES

To assess the impact of bone growth on the flexion contracture angle at the knee, to measure the bone growth pattern in rats, and to assess the impact of immobility on bone growth.

DESIGN

Experimental, controlled study.

SETTING

Bone and joint laboratory.

ANIMALS

Sixty Sprague-Dawley rats.

INTERVENTIONS

Knee joints of 40 rats were immobilized unilaterally in flexion. Sham-operated animals (n = 20) were controls.

MAIN OUTCOME MEASURES

The contracture angle and the femur and tibia lengths on radiographs.

RESULTS

The angle of flexion increased over time and was largely explained by bone growth (r =.725, p <.01). Femur and tibia grew in rats until they were 11 months old. Immobility enhanced growth in bone length, especially of the femur, after 16 and 32 weeks of immobility (p <.05).

CONCLUSIONS

Knee flexion contracture angle increased as a consequence of normal bone growth, a situation that is also encountered in skeletally immature children. The continued growth in length of bones in children may influence the progression of contractures and add to the therapeutic challenge. Ongoing bone growth should be considered when interpreting reports that use animal models for bone and joint diseases.

Do associated reactions in the upper limb after stroke contribute to contracture formation?

OBJECTIVE

To establish (1) whether associated reactions could contribute to contracture formation and (2) whether the presence of spasticity was essential for their expression, after stroke.

SUBJECTS

Subjects were 24 hemiparetics within 13 months of a stroke, unselected for contracture or spasticity.

MAIN OUTCOME MEASURES

Associated reactions were identified by the presence of muscle activity in the affected biceps brachii and quantified as the amount of affected elbow flexor torque produced during a moderate contraction of either the contralateral biceps brachii or the contralateral quadriceps muscles. Contracture was measured as loss of elbow joint range of motion and spasticity as the presence of abnormal reflex activity.

RESULTS

Associated reactions were present in at least one testing condition in seven subjects. During contractions of the contralateral biceps brachii, the median amount of elbow flexor torque produced was 0.39 (interquartile range, IQR 2.5) Nm while during contractions of the contralateral quadriceps muscle it was 0.19 (IQR 1.6) Nm. Associated reactions were not associated with contracture (p = 0.39) which was present in over half of the subjects. The incidence of associated reactions was about the same as that of spasticity, but the two were not related (p = 0.61).

CONCLUSIONS

Even though associated reactions were present in 29% of the subjects during moderate contraction of the contralateral muscles, they were not large, nor were they associated with contracture or spasticity, suggesting that this phenomenon is not usually a major problem for everyday function after stroke.

Use of Ilizarov external fixator to treat joint pterygia

Joint pterygia are rare conditions characterized by joint-flexion contractures and webbing of the overlying skin and subcutaneous structures. Treatment is difficult because the neurovascular bundle is often displaced into the web, and only moderate success has been reported with past treatment options. A retrospective review was performed on five patients with six involved joints: two antecubital pterygia and four popliteal pterygia. The Ilizarov technique was used for gradual correction of pterygia through the joint (arthrodiastasis). Primary treatment goals included improvement in functional extension, hygiene independence, and cosmesis. Ambulation was also an objective in the patients with popliteal pterygia. For inclusion in this study, a minimum of 2 years' follow-up was required after the device was removed. Preoperative goals were met in four of the six joints. Initial improvement in total arc of motion was noted; however, some regression was common. Complications were frequent, and there was a learning curve for proficiency with the Ilizarov technique. We believe that the Ilizarov technique provides a treatment option for antecubital and popliteal pterygia.

Enhanced expression of the alpha 7 beta 1 integrin reduces muscular dystrophy and restores viability in dystrophic mice

Muscle fibers attach to laminin in the basal lamina using two distinct mechanisms: the dystrophin glycoprotein complex and the alpha 7 beta 1 integrin. Defects in these linkage systems result in Duchenne muscular dystrophy (DMD), alpha 2 laminin congenital muscular dystrophy, sarcoglycan-related muscular dystrophy, and alpha 7 integrin congenital muscular dystrophy. Therefore, the molecular continuity between the extracellular matrix and cell cytoskeleton is essential for the structural and functional integrity of skeletal muscle. To test whether the alpha 7 beta 1 integrin can compensate for the absence of dystrophin, we expressed the rat alpha 7 chain in mdx/utr(-/-) mice that lack both dystrophin and utrophin. These mice develop a severe muscular dystrophy highly akin to that in DMD, and they also die prematurely. Using the muscle creatine kinase promoter, expression of the alpha 7BX2 integrin chain was increased 2.0-2.3-fold in mdx/utr(-/-) mice. Concomitant with the increase in the alpha 7 chain, its heterodimeric partner, beta 1D, was also increased in the transgenic animals. Transgenic expression of the alpha 7BX2 chain in the mdx/utr(-/-) mice extended their longevity by threefold, reduced kyphosis and the development of muscle disease, and maintained mobility and the structure of the neuromuscular junction. Thus, bolstering alpha 7 beta 1 integrin-mediated association of muscle cells with the extracellular matrix alleviates many of the symptoms of disease observed in mdx/utr(-/-) mice and compensates for the absence of the dystrophin- and utrophin-mediated linkage systems. This suggests that enhanced expression of the alpha 7 beta 1 integrin may provide a novel approach to treat DMD and other muscle diseases that arise due to defects in the dystrophin glycoprotein complex. A video that contrasts kyphosis, gait, joint contractures, and mobility in mdx/utr(-/-) and alpha 7BX2-mdx/utr(-/-) mice can be accessed at http://www.jcb.org/cgi/content/full/152/6/1207.

Dystonia in corticobasal degeneration

OBJECTIVE

To characterize the clinical features, particularly dystonia, in patients with clinically diagnosed or pathologically proven corticobasal degeneration (CBD).

BACKGROUND

Although dystonia has been reported in many neurodegenerative disorders, it has not been studied in CBD. Dystonia, often accompanied by painful rigidity and fixed contractures, is one of the most disabling features of CBD.

METHODS

The medical records, imaging studies, and videotapes of 66 patients who satisfied the clinical criteria of CBD, evaluated between 1988 and 1998, were reviewed. The occurrence, nature, and distribution of dystonic features were analyzed and correlated with other features of CBD.

RESULTS

Of the 66 patients with CBD, 39 (59.0%) had dystonia. The mean age at onset of initial symptoms was 63.9 years (range 44--75). In 20 (51.0%) patients, dystonic symptoms began in one arm, while 13 (33.0%) patients had initial leg involvement. At least one arm was affected in 36 (92.0%) dystonic patients. Although 11 (28.0%) patients had leg dystonia, the leg was the predominant site of involvement in only 1 patient. Only 12 (31.0%) patients had dystonia involving the head, neck, or trunk in the course of the disease. The diagnosis of CBD was confirmed in all 4 patients who had autopsies.

CONCLUSION

In this large series of CBD patients we found that asymmetric limb dystonia, particularly affecting one arm, is a common manifestation of CBD; dystonia may be the initial manifestation of this neurodegenerative disorder. Axial or leg dystonia, without significant involvement of an arm, is rare. There is no effective treatment for this relentless disorder, except for temporary relief of dystonia and pain, with local botulinum toxin injections.

The effect of local application of mitomycin-C on the development of capsule around silicone implants in the breast: an experimental study in mice

In this experimental study on mice we try to prove that capsule formation around breast implants is considerably diminished after topical application of Mitomycin-C (MMC). MMC solution is applied under the breast tissue or pectoralis major muscle, in the pocket of the silicone implant and just before placing it. This is a morphological study of the connective tissue formed around the implant, under light and electron microscope. Our results suggest that it is worthwhile working on a clinical study trying to prevent the most common complication of breast implants, contracture of a capsule.

KERATINOCYTE-DRIVEN CONTRACTION OF RECONSTRUCTED HUMAN SKIN

We have previously reported that reconstructed human skin, using deepidermized acellular sterilized dermis and allogeneic keratinocytes and fibroblasts, significantly contracts in vitro. Contracture of split skin grafts in burns injuries remains a serious problem and this in vitro model provides an opportunity to study keratinocyte/mesenchymal cell interactions and cell interactions with extracted normal human dermis. The aim of this study was to investigate the nature of this in vitro contraction and explore several approaches to prevent or reduce contraction. Three different methodologies for sterilization of the dermal matrix were examined: glycerol, ethylene oxide and a combination of glycerol and ethylene oxide. While the nature of the sterilization technique influenced the extent of contraction and thinner dermal matrices contracted proportionately more than thicker matrices, in all cases contraction was driven by the keratinocytes with relatively little influence from the fibroblasts. The contraction of the underlying dermis did not represent any change in tissue mass but rather a reorganization of the dermis which was rapidly reversed (within minutes) when the epidermal layer was removed. Pharmacological approaches to block contraction showed forskolin and mannose-6-phosphate to be ineffective and ascorbic acid-2-phosphate to exacerbate contraction. However, Galardin, a matrix metalloproteinase inhibitor and keratinocyte conditioned media, both inhibited contraction.

Five-year experience on ultrasonic treatment of breast contractures

The authors report their experience in five years of treating breast implant capsular contractures with an external ultrasonic device that facilitates the closed capsulotomy technique. A set of 52 patients have been treated with a 82.6% of improvement at a year follow up. Methods of application and results are discussed.

Treatment of upper motoneuron plantarflexion contractures by using an adjustable ankle-foot orthosis

OBJECTIVE

To assess the effectiveness of an adjustable ankle-foot orthosis in the treatment of plantarflexion contractures after central nervous system injury or disease.

DESIGN

Prospective, nonrandomized, interventional trial.

SETTING

University medical center's acute inpatient rehabilitation hospital.

PARTICIPANTS

Nine ankles with plantarflexion contractures that could not be passively reduced to less than neutral position occurring in 6 patients with stroke or other acquired brain injury.

INTERVENTION

To assure differentiation between spastic deformity and true contracture, patients received a 2% lidocaine block of the posterior tibial nerve. The adjustable ankle-foot orthosis was then applied on the affected ankle for 23 hours per day for 14 days. Adjustments to increase dorsiflexion passive range of motion (PROM) ranged from 0 degrees to 4.5 degrees and were attempted every 48 to 72 hours.

MAIN OUTCOME MEASURES

Dorsiflexion PROM at the ankle with the knee extended.

RESULTS

Increased PROM (average, 20.1 degrees; range, 6 degrees--36 degrees ) was statistically significant (p =.0078). Complications related to pressure with erythema or blister formation associated with pain occurred in 44% of treated ankles at some time during the 2-week trial period.

CONCLUSION

Plantarflexion contractures can be significantly reduced by using the adjustable ankle-foot orthosis with minimal complications.

Dual X-ray absorptiometry assessment of body composition in children with altered body posture

Many children have contractures and/or deformities that preclude positioning in a fully supine position. The purpose of this study was to evaluate the effects of "poor" positioning on the assessment of body composition with dual X-ray absorptiometry (DXA) in thirty-seven normal child volunteers ages 3-16 yr. Multiple whole-body DXA scans of each child were performed: duplicate scans in the correct fully supine position, two scans while simulating different positions typical of children with contractures, and a scan while positioned in the full lateral position as a "worst-case" scenario. Also evaluated were the precision of duplicate measures in the altered positions, the effect of knee flexion contractures, and the impact of metallic orthopedic fixation devices. Errors in body composition assessment did occur from "poor" positioning. In those positions simulating children with contractures, the mean errors were 4-6% for measures of bone mineral content, 1-3% for lean body mass, and 5-11% for fat mass. Measures in the correct fully supine position and the contracted positions were highly correlated. The errors obtained by altering position were small. If errors of this magnitude are of significance, then corrective equations could be utilized to improve accuracy. Precise and reasonably accurate measures of body composition can be obtained with DXA in children with disabilities and deformities that preclude fully supine positioning.

Dorsiflexion contracture after the Weil osteotomy: results of cadaver study and three-dimensional analysis

For metatarsalgia caused by a dislocated lesser metatarsophalangeal (MTP) joint and isolated over-long lesser metatarsals, surgical treatment options without sacrificing the joint are limited. Recently, the Weil osteotomy has been advocated for the treatment of this deformity. In our experience, preliminary results with this technique have revealed a high rate of dorsiflexion contracture of the MTP joints at follow-up. We performed a cadaver study and a three-dimensional analysis on sawbones to investigate this phenomenon. In the cadaveric portion of this study, the second MTP joints of two fresh-frozen cadavers were dissected; the entire ray, with the metatarsal shaft, MTP joint, toe, and plantar fascia, was removed en bloc. After gross anatomic structures were photographed, a Weil osteotomy was performed at 25 degrees relative to the long axis of the metatarsal shaft. The positions of muscles, ligaments, and tendons were noted and photographed before and after the osteotomy. In the sawbones portion of this study, a Weil osteotomy was performed at four different angles (25 degrees, 30 degrees, 35 degrees, and 40 degrees) relative to the long axis of the metatarsal. To ensure reproducibility, the sawbone models were fixed proximally to a vertical milling machine with the second metatarsals inclined 15 degrees to simulate the anatomic position. After making the cut, the plantar fragment was translated along the dorsal fragment proximally for a distance of 5 mm. Before and after the osteotomy, selected x, y, and z coordinates were obtained using a Microscribe 3D digitizer. Data analysis was performed with Microsoft Excel, and ANOVA was used to determine significant differences (p < 0.05) between the various osteotomies. Analysis of the cadaver dissection revealed that after the Weil osteotomy, the tendons of the interosseous muscles move dorsally with respect to the axis of the MTP joint due to the depression of the plantar fragment of the metatarsal. The loss of their flexion effect on the joint permits the pull of the extensor to dorsiflex the toe. The size of the depression for the various osteotomies averaged: 25 degrees osteotomy, 3.03 mm (range, 1.8 to 3.8 mm); 30 degrees osteotomy, 3.2 mm (range, 1.9 to 4.0 mm); 35 degrees osteotomy, 3.5 mm (range, 1.7 to 5.7 mm); and 40 degrees osteotomy, 4.2 mm (range, 2.8 to 6.4 mm). Amounts of shortening relative to the long axis of the metatarsal for the various osteotomies averaged: 25 degrees osteotomy, 5.03 mm (range, 4.77 to 5.30 mm); 30 degrees osteotomy, 4.59 mm (range, 3.47 to 5.19 mm); 35 degrees osteotomy, 4.27 mm (range, 2.87 to 5.00 mm); and 40 degrees osteotomy, 3.65 mm (range, 3.20 to 4.31 mm). According to our analysis, depression of the plantar fragment always occurs after a Weil osteotomy. This depression changes the center of rotation of the MTP joint, and the interosseous muscles then act more as dorsiflexors than as plantarfexors.

The effect of static traction and orthoses in the treatment of knee contractures in preschool children with juvenile chronic arthritis: A single-subject design

OBJECTIVE

External applied devices are sometimes used in the treatment of persistent knee contractures in juvenile chronic arthritis (JCA). This study examined the effect of static night traction and orthoses on passive and active extension range of motion (ROM) in preschool children with JCA.

METHOD

A single-subject design was used, comparing the outcome of periods without intervention (A) with that of periods with intervention in the form of traction and orthoses (B). Five patients, 3 girls and 2 boys, participated. Active and passive extension ROM was measured weekly. The data were examined by visual inspection of trend, slope, and mean level in each period.

RESULTS

Greater improvement in both active and passive extension ROM was seen in the B periods than in the A periods. The intervention was not observed to have any negative effects on the children.

CONCLUSION

Static night traction may be a useful supplement to physiotherapy and medication to reduce knee flexion contractures in small children with JCA. The effect of the orthoses was difficult to evaluate because they were used for an insufficient time.

Accuracy of soft tissue balancing in total knee arthroplasty

To the best of our knowledge, this is the first study to assess the accuracy of balancing of the flexion and extension gaps in total knee arthroplasty (TKA). Measurements of the heights of the flexion and extension gaps were obtained during 104 consecutive primary, posterior-stabilized TKAs in osteoarthritic patients. Clinically, all knees appeared to be well balanced intraoperatively. Rectangular flexion and extension gaps almost always were obtained within 1 mm (84%-89%). None of the knees was >3 mm from being perfectly rectangular. Equality of the flexion and extension gaps was more difficult to obtain (47%-57% were within 1 mm). With meticulous attention, perfect soft tissue balance is not always achieved in TKA.

The outcome of Erb's palsy when the decision to operate is made at 4 months of age

Since the establishment of the obstetrical brachial plexus clinic in Saudi Arabia, the author has designed a prospective study in which the indication for brachial plexus surgery in infants with Erb's palsy was the lack of active elbow flexion against gravity at 4 months of age. Forty-three infants were included in the study and were distributed among four groups: group A (n = 20) included infants who had active elbow flexion at the initial assessment or at 2 months of age; group B (n = 9) included infants who had active elbow flexion at 3 months of age; group C (n = 11) included infants who had active elbow flexion at 4 months of age; and group D (n = 3) included infants who did not have active elbow flexion at 4 months of age. At the final follow-up, all children in group A demonstrated complete spontaneous recovery of the motor power of the limb. All children in group B also had satisfactory spontaneous recoveries, and none required secondary corrective procedures. Five of the 11 patients in group C had satisfactory spontaneous recoveries. The remaining six children in group C had good recovery of elbow flexion but a poor recovers of shoulder function. Finally, all three patients who did not have elbow flexion at 4 months of age (group D) underwent surgical exploration and reconstruction of the brachial plexus, using nerve grafts. The results of this prospective study are discussed, along with the controversial issue regarding the timing of primary plexus surgery in Erb's palsy.

Arthrofibrosis after total knee arthroplasty

Six total knee arthroplasties in five patients were revised because of persistent limited motion after the primary arthroplasty. All of the revised implants were of an appropriate size and not malpositioned. No cause of stiffness was identified other than soft tissue contracture. Four of the components were posterior cruciate retaining and two were posterior cruciate substituting. Heterotopic bone formation was observed in two knees before the revision surgery and five knees after the revision surgery. Arc of motion was increased from 36 degrees (range, 20 degrees-70 degrees) before revision surgery to 86 degrees (range, 70 degrees-110 degrees) after revision surgery. What triggers the proliferation of extensive scar tissue formation in patients with arthrofibrosis is not clear. Some patients may be predisposed to this condition or may have it develop as a response to the surgical trauma and postoperative rehabilitation. However, when arthrofibrosis does develop after total knee arthroplasty, some improvement in motion and pain can be achieved with revision surgery.

[Functional gait adaptations in patients with painful hip]

PURPOSE OF THE STUDY

This prospective study was conducted to analyze the mechanisms of gait compensation in patients with painful hip and to search for correlations with preoperative clinical and radiographic findings.

MATERIAL AND METHODS

Optoelectronic and multicomponent force-plate datas were used to calculate joint motion, moments and intersegmental forces for 26 patients with unilateral hip pain and 20 normal age and sex-matched patients. Height was similar in the two groups but mean weight in the study group (83 kg) was greater than in the controls (68 kg). The preoperative Harris score was 53 in the study group and 16 patients had a permanent flexion contracture of the knee (mean 15 degrees, range 5-30 degrees). Radiographically, there were 22 cases of osteo-arthritis hip disease and 4 cases of necrosis.

RESULTS

Gait analysis showed a significant 0.66 +/- 0.06 m (12 p. 100) reduction in step length. Patients who had severe hip pain walked with a decreased dynamic range of motion (18 +/- 5 degrees, p<0.0001) with a curve reversal as they extended the hip. They also reduced dynamic range of motion of the knee and ankle. Patients who presented a reversal in their dynamic hip range of motion had a greater passive flexion contracture and a greater loss in range of motion during gait than those with a smooth regular pattern (p<0.0001). Patients with hip pain walked with significantly decreased external extension, adduction, and internal and external rotation moments (p<0.0001). They also unloaded the ipsilateral knee and ankle. The decreased hip extension moment was significantly correlated with an increased level of pain (p<0.0001). There was no correlation with radiological findings.

DISCUSSION

Reversal of dynamic hip range of motion was interpreted as a mechanism to increase effective hip extension during stance phase through increased anterior pelvic tilt and lumbar lordosis.

CONCLUSION

Patients with painful hip walked with a manner that was asymmetric. These gait modifications were related to hip limitation in passive motion and pain. Patients with flexion contracture adopted a compensatory gait mechanism. This study confirms relation between hip pain and forces across the hip joint.

Clinical and molecular genetic spectrum of autosomal dominant Emery-Dreifuss muscular dystrophy due to mutations of the lamin A/C gene

Emery-Dreifuss muscular dystrophy (EDMD) is characterized by early contractures of the elbows and Achilles tendons, slowly progressive muscle wasting and weakness, and life-threatening cardiomyopathy with conduction blocks. We recently identified LMNA encoding two nuclear envelope proteins, lamins A and C, to be implicated in the autosomal dominant form of EDMD. Here, we report on the variability of the phenotype and spectrum of LMNA mutations in 53 autosomal dominant EDMD patients (36 members of 6 families and 17 sporadic cases). Twelve of the 53 patients showed cardiac involvement exclusively, although the remaining 41 all showed muscle weakness and contractures. We were able to identify a common phenotype among the patients with skeletal muscle involvement, consisting of humeroperoneal wasting and weakness, scapular winging, rigidity of the spine, and elbow and Achilles tendon contractures. The disease course was generally slow, but we observed either a milder phenotype characterized by late onset and a mild degree of weakness and contractures or a more severe phenotype with early presentation and a rapidly progressive course in a few cases. Mutation analysis identified 18 mutations in LMNA (i.e., 1 nonsense mutation, 2 deletions of a codon, and 15 missense mutations). All the mutations were distributed between exons 1 and 9 in the region of LMNA that is common to lamins A and C. LMNA mutations arose de novo in 76% of the cases; 2 of these de novo mutations were typical hot spots, and 2 others were identified in 2 unrelated cases. There was no clear correlation between the phenotype and type or localization of the mutations within the gene. Moreover, a marked inter- and intra-familial variability in the clinical expression of LMNA mutations exists, ranging from patients expressing the full clinical picture of EDMD to those characterized only by cardiac involvement, which points toward a significant role of possible modifier genes in the course of this disease. In conclusion, the high proportion of de novo mutations together with the large spectrum of both LMNA mutations and the expression of the disease should now prompt screening for LMNA in familial and sporadic cases of both EDMD and dilated cardiomyopathy associated with conduction system disease.

Both dermal matrix and epidermis contribute to an inhibition of wound contraction

Contracture is a major detriment to functional recovery from large wounds. To determine the relative value of dermal replacement and epidermal coverage in inhibiting wound contraction, five full-thickness wounds (all 5 x 5 cm2) were placed on the back of 8 swine and treated in the following manner: (1) open wound, (2) porcine acellular dermis (analogous to AlloDerm for human use), (3) porcine acellular dermis with epidermal autograft placed 7 days postwounding, (4) porcine acellular dermis with immediate epidermal autograft, and (5) conventional-thickness autograft. Scar dimensions and punch biopsies were taken at days 14 and 30 postwounding. The planimetry results demonstrated that wound contraction was significantly greater with the open wounds (group 1) than all other wounds with a dermal substitute. Furthermore, wounds with initial epidermal coverage had significantly less contraction than unepithelialized wounds (14.8 +/- 1.1 cm2 at day 14 in wound group 2 vs. 20.4 +/- 0.6 cm2 in wound group 4; p < 0.05). Biopsy results revealed that wounds with initial epithelial coverage had the least amount of inflammation. These findings suggest that both dermal matrix and epidermal coverage contribute to an inhibition of wound contraction and that prompt epithelial coverage appears to impede contraction by reducing inflammation.