H. van Mameren

The effectiveness of manual therapy, physiotherapy, and treatment by the general practitioner for nonspecific back and neck complaints : a randomized clinical trial

In a randomized trial, the effectiveness of manual therapy, physiotherapy, continued treatment by the general practitioner, and placebo therapy (detuned ultrasound and detuned short-wave diathermy) were compared for patients (n = 256) with nonspecific back and neck complaints lasting for at least 6 weeks. The principle outcome measures were severity of the main complaint, global perceived effect, pain, and functional status. These are presented for 3, 6, and 12 weeks follow-up. Both physiotherapy and manual therapy decreased the severity of complaints more and had a higher global perceived effect compared to continued treatment by the general practitioner. Differences in effectiveness between physiotherapy and manual therapy could not be shown. A substantial part of the effect of manual therapy and physiotherapy appeared to be due to nonspecific (placebo) effects.

Cervical spine motion in the sagittal plane. II. Position of segmental averaged instantaneous centers of rotation--a cineradiographic study.

Anteflexion and retroflexion movements of the cervical spine were recorded cineradiographically during three measuring sessions to determine reproducibility as well as intraindividual and interindividual variability of segmental instantaneous centers of rotation [recorded as “averaged” and “standard”). Segmental averaged instantaneous centers of rotation were based on data obtained from all frames of the cineradiographic film by the use of the average pentagon and moving average method. Only the first and last frame were used to construct the segmental standard instantaneous centers of rotation. Contrary to segmental range of motion, a parameter of quanityt of motion, the position of the averaged Instantaneous centers of rotation (better than the standard), a parameter of quality of movements, shows a variability of such low extent that it seems feasible to use it to diagnose abnormal mobility or in assessing therapy in the neck region.

No effect of bipolar interferential electrotherapy and pulsed ultrasound for soft tissue shoulder disorders: a randomised controlled trial

OBJECTIVE To assess the efficacy of bipolar interferential electrotherapy (ET) and pulsed ultrasound (US) as adjuvants to exercise therapy for soft tissue shoulder disorders (SD). METHODS Randomised placebo controlled trial with a two by two factorial design plus an additional control group in 17 primary care physiotherapy practices in the south of the Netherlands. Patients with shoulder pain and/or restricted shoulder mobility, because of a soft tissue impairment without underlying specific or generalised condition, were enrolled if they had not recovered after six sessions of exercise therapy in two weeks. They were randomised to receive (1) active ET plus active US; (2) active ET plus dummy US; (3) dummy ET plus active US; (4) dummy ET plus dummy US; or (5) no adjuvants. Additionally, they received a maximum of 12 sessions of exercise therapy in six weeks. Measurements at baseline, 6 weeks and 3, 6, 9, and 12 months later were blinded for treatment. Outcome measures: recovery, functional status, chief complaint, pain, clinical status, and range of motion. RESULTS After written informed consent 180 patients were randomised: both the active treatments were given to 73 patients, both the dummy treatments to 72 patients, and 35 patients received no adjuvants. Prognosis of groups appeared similar at baseline. Blinding was successfully maintained. At six weeks seven patients (20%) without adjuvants reported very large improvement (including complete recovery), 17 (23%) and 16 (22%) with active and dummy ET, and 19 (26%) and 14 (19%) with active and dummy US. These proportions increased to about 40% at three months, but remained virtually stable thereafter. Up to 12 months follow up the 95% CI for differences between groups for all outcomes include zero. CONCLUSION Neither ET nor US prove to be effective as adjuvants to exercise therapy for soft tissue SD.

Scarf versus chevron osteotomy in hallux valgus: a randomized controlled trial in 96 patients.

Background: The degree of correction of hallux valgus deformity using a distal chevron osteotomy is reported as limited. The scarf osteotomy is reported to correct large intermetatarsal angles (IMA). The purpose of this study was to evaluate if one technique gave greater correction of the IMA and hallux valgus angle (HVA) than the other. Methods: After informed consent, 96 feet in 83 patients were randomized into two treatment groups (49 scarf and 47 chevron osteotomies). The results were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Valgus Scale and radiographic HVA and IMA measurements. Results: At 27 (range 23–31) months followup both groups improved. The AOFAS score in the chevron group improved from 48 to 89 points and in the scarf group from 47 to 91 points. In the chevron group the HVA corrected from 30 to 17 degrees, and in the scarf group the HVA corrected from 29 to 18 degrees. In both groups, the IMA was corrected from 13 to 10 degrees. The differences were not statistically significant. Three patients in the chevron group developed a partial metatarsal head necrosis. In the scarf group, four patients developed grade 1 complex regional pain syndrome compared to one patient in the chevron group. Conclusions: No differences of statistical significance could be measured between the two groups with respect to the AOFAS score, HVA, and IMA. Although both groups showed good to excellent results, we favor the chevron osteotomy because the procedure is technically less demanding.

On the pathogenesis of brain tumour cysts: a volumetric study of tumour, oedema and cyst

Abstract Chemical analysis of brain tumour cyst contents has invalidated the concept of cyst formation being the result of tumour necrosis, and a common mechanism of vasogenic brain oedema and cyst formation, namely blood-brain barrier (BBB) disruption, has been suggested. To analyse a possible relationship between the occurrence of vasogenic oedema and the presence of cysts, we performed a volumetric analysis on the MRI and CT studies of 60 patients with primary or metastatic brain tumours. We compared four groups of tumours: 30 gliomas, of which 15 were cystic and 15 not and 30 metastatic brain tumours of which 15 were cystic and 15 not. Although the mean volume of oedema was similar for cystic and noncystic tumours, the ratio of oedema to tumour volume was approximately four times as high in cystic supratentorial tumours. This would support the view that cyst formation may be related to relatively greater production of oedema, possibly due to fusion of microcysts containing oedema fluid. The ratio of oedema to tumour volume is not greater in cystic cerebellar and intraventricular tumours. This may be due to the different anatomical organization of the cerebellar white matter, and the fact that the intraventricular tumours are bordered by subcortical grey matter. In these cases, spread of oedema is impeded. Formation of a large amount of brain oedema is therefore not an essential prerequisite for cyst formation.

Long-term foreign-body reaction to preperitoneal polypropylene mesh in the pig

SummaryThe aim of the study is to establish the long-term foreign-body reaction to a polypropylene mesh used for inguinal hernia repair in a pig model. Twenty-two Surpipro® meshes were implanted in 22 preperitoneal inguinal areas in 11 female 10-week-old Yorkshire and Dutch landway swine. The prosthetic mesh was implanted using a laparoscopic transperitoneal technique. At 1, 2, 3, 4, 6, 12 and 26 weeks, the animals were sacreificed and the number of foreign-body giant-cells at the mesh-tissue interface was counted. The mean numbers of giant-cells (SD) after 1, 2, 3, 4, 6, 12 and 26 weeks were: 0.9 (2.4), 7.3 (5.4), 19 (8.2), 15.2 (7.9), 15.9 (6.9), 14.1 (5.6), and 8.2 (4.7). The mean number of giant-cells at 12 weeks was significantly lower than at 3 weeks. The mean number of giant-cells at 26 weeks was significantly lower than at 3, 4, 6, and 12 weeks. We conclude that the foreign-body giant-cell reaction to polypropylene mesh increases until the third week after implantation. Thereafter, it gradually decreases, and at six months it persists at half the maximal level at 3 weeks.

The internal vertebral venous plexus prevents compression of the dural sac during atlanto-axial rotation

Abstract Deformation of the extradural space and the possibility of impression upon the dural sac during atlanto-axial rotation are investigated. Atlanto-axial rotation leads to a reduction in the cross-sectional area of the bony spinal canal of approximately 40 %. Atlanto-axial rotation was recorded by endocanalar views from a video camera fixed inside the skull of six unembalmed cadavers. Axial thin-section T1-weighted MRI slice sets were acquired from three volunteers (mid-position and maximal left and right rotation of the head and cervical spine). The axial cross-sectional areas of the bony spinal canal, dural sac and spinal cord were measured. In two other persons post-gadolinium contrast-enhanced T1-weighted MRI volume scans with fat-suppression prepulse were acquired (mid-position and rotation) to determine venous contents of the extradural space. The 50:50 ratio between left and right extradural halves in mid-position changed to an ipsilateral:contralateral ratio of 20:80 in maximum rotation at the level just above the lateral C1-C2 joints. Directly below these joints the opposite occurred. The post-contrast studies showed an enhancing internal vertebral venous plexus (IVVP), which almost completely occupied the extradural space at the atlanto-axial level. This could not be shown in the cadaver experiments, because of absence of blood and cerebrospinal fluid (CSF) pressure. During atlanto-axial rotation blood displacement in the IVVP allows major deformations of the extradural space. This prevents dural sac impression.

Changes of the soft tissue of the forefoot during loading: a volumetric study

Abstract Background : Although complaints of the forefoot are frequent, little is known about the changes in the soft tissue of the forefoot that take place during loading. Objective : To study the volume changes of the soft tissue of the forefoot in reaction to loading in normal volunteers and to compare it to the described changes in the heel pad. Method : With computed tomography (CT), the volume distribution of the soft tissue of the right forefoot of 11 healthy volunteers was examined in unloaded and in loaded posture. Results : The decrease of the overall volume of the forefoot (4.8%) in the loaded posture was located on the plantar side. A small increase in volume (1.6%) occurred on the dorsal side of the forefoot at the metatarsal (MT) level. Conclusions : The changes in soft tissue volume distribution in the forefoot by loading resemble observations in the heel region. The increase in volume on the dorsal side is unique for the forefoot and likely reflects a dorsal shift of soft tissue in the intermetatarsal spaces. The decrease in the overall volume was due to compression of plantar venous structures. Both observations may have an important function in shock absorption. In normal volunteers, the volume differences are so prominent that the described procedure may find clinical use in early identification of tissue damage.

Patients’ adherence to a walking programme for non-specific low back pain

Abstract The aim of this cross-sectional observational study was to investigate adherence rate and factors influencing the adherence in following home-based activity advice, in patients referred to a physiotherapy clinic for non-specific low back pain. Research suggests that inadequate adherence to home-based activity advice during an intervention period may diminish treatment outcomes. Factors negatively influencing adherence appeared to be related to a persons beliefs and perceptions. Perceived barriers, low self-efficacy and unbeneficial illness beliefs have been consistent predictors for non-adherence across studies. 51 patients who reported non-specific low back pain were advised to walk daily. Physical activity was measured with a validated triaxial seismic accelerometer. The effect of multiple patient-related determinants on the rate of adherence was studied. Only four out of 51 patients (8%) fully adhered to the walking advice. In this study, there were no significant effects of patient-related determinants on the rate of adherence. Factors negatively influencing adherence behaviour were lack of time, weather conditions and increasing low back pain. In conclusion, patient adherence in following home-based activity advice for non-specific low back pain outside the clinical setting is poor.

Impact of muscle contraction upon head stabilisation during forward acceleration

Abstract Introduction: The impact of muscle contraction upon head movements induced by a forward acceleration was studied as a model for low impact car-accidents. The purpose of our research is to examine: (i) whether and by which mechanism neck muscle contraction is induced after onset of the movement; and (ii) if voluntary neck muscle contraction prior to the movement affects head motion. Subjects and methods: Eight healthy volunteers (mean age 21.4 years) were included in this study. Volunteers were sitting on a standard car seat mounted on a sled. The computer-controlled, motor-driven sled was forward accelerated with 0.6 g. In test series 1, head and body movement were detected with a standard video camera (20 ms per frame) and accelerometers mounted on the head without interference with muscle activity. Muscle activation was detected by simultaneous measurement of surface EMG of m. splenius capitis, m. trapezius (descending part), m. scalenis medius, m. sternocleido mastoideus, m. digastricus (anterior belly), m. mylohyoideus, m. pectoralis major, m. quadriceps, tibialis anterior and triceps surae. The subjects movements and muscle activity were examined during forward sled acceleration when: (i) the subjects were relaxed and could not anticipate the precise start of sled acceleration; (ii) when they contracted all body muscles for about 4 s prior to and during the sled acceleration; and (iii) when head and trunk were fixed to the chair. The same subjects were accelerated in test series 2, but now head and trunk movements were measured with a better time resolution by use of a high-speed video camera (500 Hz) and accelerometers mounted on the head (bite board), body and sled. Head and body movements were measured under conditions 1 and 2 as described above. Reproducibility was tested by repeating each test condition once, including repositioning of the subjects, the accelerometers and body fixed sell spot markers. Results and conclusions: The current experimental set-up allows a low-cost evaluation of head and body movements induced by low impact velocity impulses. We observed that sudden whole body acceleration induces head accelerations that exceed the acceleration of the impact by a factor of 2–3-fold. After the impact, the head first remains stationary in space while the sled and trunk move forward (relative head and upper trunk translation). Subsequently, head and trunk rotate backwards, ultimately followed by an additional retroflexion of the head alone. Precontraction and anticipation of the impact leads to a faster increase of general muscle tone. It does not affect the initial translation but leads to a reduction of about 30–35% of head rotations and head angular velocities. The muscle contraction is most like a generalised alerting response. It should be noted that the current results were obtained at a loading level of 0.7 g, which is far below the 5–12 g levels observed in rear-end collisions. Since the current study shows only small influences of the muscle contraction, it is assumed that the contraction will not be strong enough to limit the larger head and trunk motion with greater impacts and does not reduce the probability of getting a whiplash injury.