Reliability of in vivo determination of forearm muscle volume using 3.0 T magnetic resonance imaging.

PURPOSE: To apply magnetic resonance imaging (MRI) as a tool for quantifying muscle volume of forearm muscles feasibility and reliability of volume estimation of the flexor carpi ulnaris (FCU) and the extensor carpi ulnaris (ECU). MATERIALS AND METHODS: Forearms of 10 subjects were scanned twice. Muscle volumes were calculated from manual outlines on axial slices, slice thickness, and the number of slices. Observer agreement and repeatability were estimated using intraclass correlation, coefficient of variation, and the smallest detectable difference. RESULTS: The average volume of the FCU and ECU was 31.0 mL (SD 11.5 mL) and 16.4 mL (SD 7.7 mL), respectively. Intraclass correlation coefficients of the volumes were all above 0.99 and the coefficient of variation varied between 5.7% and 0.8%. The smallest detectable difference corresponded to approximately 7% of muscle volume. CONCLUSION: MRI muscle volume measurement of forearm muscles is feasible, reproducible, and allows for longitudinal studies where expected responsiveness exceeds 7%.

Long-Term Functional Results of a Wrist Exercise Program for Patients with Palmar Midcarpal Instability.

Background Patients with palmar midcarpal instability have symptoms of pain, combined with clinical signs of abnormal mobility on stressing the joint, an unpredictable blockade feeling, and a noticeable clunk, in the absence of an underlying trauma. No data are available on the effect of conservative treatment for these patients. Purpose The purpose of this study was to evaluate the effect and the long-term functional outcomes of a wrist exercise program in patients with palmar midcarpal instability. Patients and Methods All patients diagnosed with palmar midcarpal instability between 2005 and 2011 were included. Patients completed the Patient-Rated Wrist and Hand Evaluation (PRWHE) and the Short Form-36 health (SF-36) questionnaires, scaled their perceived pain before and after treatment, and indicated the effect of the received treatment. Results A total of 119 patients diagnosed with palmar midcarpal instability were included. The median follow-up time was 6 years (IQR 4.5-7.0). The median PRWHE score after hand therapy was 35.5 and the median mental component of the SF-36 score was 53.9 and the physical component was 45.2. The median perceived pain reduced from eight to four and the median therapeutic effect of the wrist exercise program was five. Conclusion Although palmar midcarpal instability remains to be a chronic disease, the effectiveness of our wrist exercise program is promising with acceptable long-term functional results and a good quality of life. Level of Evidence Level IV, retrospective cohort study.

Restricted upper extremity range of motion in mucopolysaccharidosis type I: no response to one year of enzyme replacement therapy.

BACKGROUND: Mucopolysaccharidosis type I (MPS I) results from deficiency of the lysosomal enzyme alpha-L: -iduronidase (IDUA). Glycosaminoglycans (GAGs) accumulate in multiple organs and the storage in connective tissues results in restricted mobility. Previous studies provided evidence of an improvement in range of motion (ROM), as measured by goniometry, after supplementation of recombinant enzyme (ERT). AIM: The aim of the study was to evaluate the efficacy of ERT in improving ROM in patients with MPS I, using a blinded three-dimensional (3D) video analysis of unrestricted movements of the upper extremities. METHODS: In 6 patients with the attenuated phenotype of MPS I, the longitudinal changes in the upper extremity ROM were analysed by 3D video analysis during one year of ERT. RESULTS: At baseline, all studied movements except for elbow flexion were restricted. No significant improvement of the restricted upper extremity ROM was observed after one year of ERT. CONCLUSION: Long-standing restrictions in ROM probably cannot be reversed by ERT. Early initiation of treatment might be essential to prevent irreversible functional defects.

Movement patterns of the upper extremity and trunk associated with impaired forearm rotation in patients with hemiplegic cerebral palsy compared to healthy controls.

The aim of this study was to objectively assess the relationship between impaired forearm rotation and movement patterns of the upper arm and trunk in patients with hemiplegic cerebral palsy. For this purpose, 'extrinsic forearm rotation' was introduced as a parameter to quantify the cumulative result of all movements that supplement forearm rotation. The results of three-dimensional video analysis of the upper extremity and trunk in different reaching tasks in eight male and two female patients (mean age, 16 years and 2 months) were compared to those of 10 case-matched controls. The active forearm rotation impairment in the patient group as compared to the controls was combined with a significantly higher value for 'extrinsic forearm rotation'. In this way, we objectively measured compensatory movement patterns associated with impaired forearm rotation and, consequently, we advocate assessment of the overall movement strategy rather than just the forearm deformity in patients with hemiplegic cerebral palsy.

[Prevalence and characteristics of haemangiomas in young children]. / Prevalentie en kenmerken van hemangiomen bij jonge kinderen.

OBJECTIVE: To obtain current data on the prevalence and characteristics of haemangiomas within a population-based group of children. DESIGN: Cross-sectional study. METHOD: During March-May 2002, all children aged 0-16 months who presented for regular check-ups at child health centres in the Tilburg area, The Netherlands, were examined by physicians for the presence of haemangiomas. The characteristics of the children with a haemangioma were recorded and parents were asked for more specific information. RESULTS: Of the 2204 children included, 219 (10) had 256 haemangiomas. The girl-boy ratio was 19:1 The haemangioma was already present at birth in 24% of children. Of the 256 haemangiomas, 15% were located subcutaneously, 33% were located in the head-neck area and 37% on the body. Of the 84 haemangiomas in the head-neck area, 75% were located on the scalp and forehead. Of the 219 children with a haemangioma, 7% and 6% visited a general practitioner or specialist regarding the haemangioma, respectively. They were consulted particularly when the haemangioma was present at birth, located subcutaneously, located in the head-neck area, and when multiple haemangiomas were present.

Biomechanical effects of dissecting flexor carpi ulnaris.

Our aim was to determine whether the length and function of the flexor carpi ulnaris muscle were affected by separating it from its soft tissue connections. We measured the length of flexor carpi ulnaris before and after its dissection in ten patients with cerebral palsy. After tenotomy, tetanic contraction shortened the muscle by a mean of 8 mm. Subsequent dissection to separate it from all soft tissue connections, resulted in a further mean shortening of 17 mm (p < 0.001). This indicated that the dissected connective tissue had been strong enough to maintain the length of the contracting muscle. Passive extension of the wrist still lengthened the muscle after tenotomy, whereas this excursion significantly decreased after subsequent dissection. We conclude that the connective tissue envelope, which may be dissected during tendon transfer of flexor carpi ulnaris may act as a myofascial pathway for the transmission of force. This may have clinical implications for the outcome after tendon transfer.

Restored flexor carpi ulnaris function after mere tenotomy explains the recurrence of spastic wrist deformity.

OBJECTIVE: To prove that fibrous restoration of the continuity of a cut tendon may cause recurrence of flexion deformity of the wrist after mere tenotomy of the spastic flexor carpi ulnaris muscle. BACKGROUND: Mere tenotomy of the flexor carpi ulnaris tendon is insufficient to prevent recurrence of acquired spastic flexion deformity of the wrist. Subsequent restoration of the continuity of the tendon by fibrous interposition may result in the recurrence. We examined whether a previously tenotomised muscle is strong enough to cause the deformity. METHODS: Active and passive force-length characteristics of the flexor carpi ulnaris muscle were measured intraoperatively in a patient with recurrent spastic flexion wrist deformity. The observed characteristics were compared with the average in vivo force-length characteristics of 14 spastic flexor carpi ulnaris muscles that had not previously been operated. RESULTS: The previously tenotomised flexor carpi ulnaris muscle was able to maximally exert 110 N force. Its active force-length curve and passive force at maximal extension were similar to those of non-operated spastic flexor carpi ulnaris muscles. CONCLUSIONS: A previously tenotomised flexor carpi ulnaris muscle is strong enough to cause recurrence of spastic flexion deformity of the wrist in case functional fibrous restoration of the tendon occurs after mere tenotomy. RELEVANCE: The surgical routine of mere tenotomy should probably be modified by including the dissection of the distal muscle belly and the excision of a segment of the tendon to avoid its restoration.

Mechanical evaluation of the Pronator Teres rerouting tendon transfer.

We simulated pronator teres rerouting using a three-dimensional biomechanical model of the arm. Simulations comprised the evaluation of changes in muscle length and the moment arm of pronator teres with changes in forearm axial rotation and elbow flexion. The rerouting of Pronator Teres was simulated by defining a path for it through the interosseous membrane with re-attachment to its original insertion. However the effect of moving the insertion to new positions, 2 cm below and above, the original position was also assessed. The effect on total internal rotation and external rotation capacity was determined by calculating the potential moments for pronator teres, supinator, pronator quadratus, biceps brachii and brachioradialis. Pronator teres was found to be a weak internal rotator in extreme pronation, but a strong internal rotator in neutral rotation and in supination. After rerouting pronator teres was only a strong external rotator in full pronation and not at other forearm positions, where the effect of rerouting was comparable to a release procedure.

Three-dimensional video analysis of forearm rotation before and after combined pronator teres rerouting and flexor carpi ulnaris tendon transfer surgery in patients with cerebral palsy.

The effect of combined pronator teres rerouting and flexor carpi ulnaris transfer on forearm rotation was prospectively studied by comparison of pre- and postoperative three-dimensional analysis of forearm range of motion in ten patients with cerebral palsy. One year postoperatively, surgery had improved maximal supination of the forearm in all patients by an average of 63 degrees, but there was also a mean loss of 40 degrees pronation. Forearm range of motion increased by a mean of 23 degrees. The centre of the range of motion on average shifted 52 degrees in the direction of supination. Based on these results of objective forearm range of motion analysis, we conclude that the common combination of pronator teres rerouting and flexor carpi ulnaris transfer in patients with cerebral palsy effectively facilitates active supination but impairs active pronation.

Why is joint range of motion limited in patients with cerebral palsy?

Patients with spastic cerebral palsy of the upper limb typically present with various problems including an impaired range of motion that affects the positioning of the upper extremity. This impaired range of motion often develops into contractures that further limit functioning of the spastic hand and arm. Understanding why these contractures develop in cerebral palsy will affect the selection of patients suitable for surgical treatment as well as the choice for specific surgical procedures. The generally accepted hypothesis in patients with spastic cerebral palsy is that the hyper-excitability of the stretch reflex combined with increased muscle tone result in extreme angles of the involved joints at rest. Ultimately, these extreme joint angles are thought to result in fixed joint postures. There is no consensus in the literature concerning the pathophysiology of this process. Several hypotheses associated with inactivity and overactivity have been tested by examining the secondary changes in spastic muscle and its surrounding tissue. All hypotheses implicate different secondary changes that consequently require different clinical approaches. In this review, the different hypotheses concerning the development of limited joint range of motion in cerebral palsy are discussed in relation to their secondary changes on the musculoskeletal system.

Biceps brachii can add to performance of tasks requiring supination in cerebral palsy patients.

The aim of this study was to assess whether cerebral palsy patients can use biceps brachii for supination during movement tasks requiring supination and pronation. 3D upper extremity kinematic and EMG-data of 12 patients (mean age 13 y 8 mo ± 36 mo) were compared to 10 healthy age-matched controls. Significant difference in biceps brachii activation between maximal isolated pronation and supination in both groups showed that it is possible for CP patients to use biceps brachii for supination. Performance of reach-to-grasp with either pronation or supination showed similar activation patterns as during isolated tasks in both groups, although increased biceps brachii activation likely also hampered performance of reach-to-grasp in the patient group by causing increased, and possibly unwanted elbow flexion. However, the functional effect of this flexion for supination purposes cannot be ruled out. Therefore, one should be cautious with simply weakening biceps brachii when the purpose is to improve functional reach. Ideally treatment might focus more on changing the flexion moment/supination moment ratio of biceps toward a stronger supination function.

Normal compartment pressures of the lower leg in children.

Compartment pressures have not previously been studied in healthy children. We compared the pressures in the four lower leg compartments of healthy children with those of healthy adults. We included patients aged between two months and six years, and measured the pressures in 80 compartments of 20 healthy children using simple needle manometry. Measurements were repeated in a control group of 20 healthy adults. The mean compartment pressure in the lower leg in children was significantly higher than in adults (p < 0.001). On average, pressures in the four compartments varied between 13.3 mmHg and 16.6 mmHg in the children and between 5.2 mmHg and 9.7 mmHg in the adults. The latter is in accordance with those recorded in the literature. The mean arterial pressure did not relate to age or to pressure in the compartment. The findings of this study that the normal compartment pressure of the lower leg in healthy children is significantly higher than that in adults may be of considerable significance in clinical decision-making in children of this age.

Movement patterns of the upper extremity and trunk before and after corrective surgery of impaired forearm rotation in patients with cerebral palsy.

The effect of surgical correction of impaired forearm rotation on associated body movement patterns was studied prospectively by comparison of preoperative and postoperative three-dimensional video analysis of the upper extremity and trunk in eight male and two female patients with hemiplegic cerebral palsy (CP; mean age 16y 2mo [SD 4y 11mo]; range 11-27y). A customized parameter, 'extrinsic forearm rotation', was used to quantify associated movements supplementing forearm rotation. After surgical correction of the pronation deformity, active forearm supination during a functional reaching task had improved by a mean of 37 degrees in combination with significantly decreased extrinsic forearm rotation by a mean of 13 degrees . In addition, an average loss of 16 degrees of active pronation in combination with increased extrinsic forearm rotation (mean 8 degrees ) was observed. On the basis of these results we conclude that successful surgical correction of a pronation deformity in patients with CP directly affects related movement patterns of the upper extremity and trunk.