Bert van Linge

Spontaneous Remodeling of the Spinal Canal After Conservative Management of Thoracolumbar Burst Fractures

Study Design. Forty‐two conservatively treated patients with a burst fracture of the thoracic, thoracolumbar, or lumbar spine with more than 25% stenosis of the spinal canal were reviewed more than 1 year after injury to investigate spontaneous remodeling of the spinal canal. Objectives. To investigate the natural development of the changes in the spinal canal after thoracolumbar burst fractures. Summary of the Background Data. Surgical removal of bony fragments from the spinal canal may restore the shape of the spinal canal after burst fractures. However, it was reported that restoration of the spinal canal does not affect the extent of neurologic recovery. Methods. Using computerized tomography, the authors compared the least sagittal diameter of the spinal canal at the time of injury with the least sagittal diameter at the follow‐up examination. Results. Remodeling and reconstitution of the spinal canal takes place within the first 12 months after injury. The mean percentage of the sagittal diameter of the spinal canal was 50% of the normal diameter (50% stenosis) at the time of the fracture and 75% of the normal diameter (25% stenosis) at the follow‐up examination. The correlation was positive between the increase in the sagittal diameter of the spinal canal and the initial percentage stenosis. There was a negative correlation between the increase in the sagittal diameter of the spinal canal and age at time of injury. Remodeling of the spinal canal was not influenced by the presence of a neurologic deficit. Conclusion. Conservative management of thoracolumbar burst fractures is followed by a marked degree of spontaneous redevelopment of the deformed spinal canal. Therefore, this study provides a new argument in favor of the conservative management of thoracolumbar burst fractures.

Stress Radiography of the Talocrural and Subtalar Joints

The object of this investigation was to determine a possible subtalar component in a group of 33 patients with chronic ankle instability. A group of 10 subjects without ankle/foot symptoms acted as controls. A standardized radiographic assessment of talar and simultaneous subtalar tilt was made. A hinge device to stress the joints and a specific subtalar stress view (Brodén view) were used under fluoroscopic control. Radiographs were made with the feet: (1) in neutral position, (2) after inversion with moderate force until the point of fair restraint (step 1), and (3) after inverting with more force as far as the conditions would allow (step 2). An increase of talar tilt between step 1 and step 2 was only found in feet that were symptomatic. This suggests that this increase is only possible when lateral ligaments are damaged. Further research is necessary to determine whether this finding can serve as a parameter to discriminate between physiological and abnormal talar tilt. A wide range of subtalar motion was found in both symptomatic and asymptomatic feet. With the present method, practically all subtalar joints showed some loss of congruity and medial shift of the calcaneus in relation to the talus. This could not be correlated with ankle instability at the talocrural joint. The consequence of the use of different subtalar stress methods has so far received little attention and is discussed.

Incidence of osteonecrosis after renal transplantation

The incidence of osteonecrosis was 24% in 248 patients who had received 262 kidney transplants 1971-1982. However, based only on patients at risk, i.e. alive with functioning transplants, the incidence at 1, 3 and 6 years was found to be 13, 27 and 36%; after six years no new cases were found. The relative increase in body-weight at 180 days was predictive as regards risk for osteonecrosis, while the cumulative dose of steroids was not. This suggests that individual sensitivity to steroids rather than the absolute cumulative dose is involved in the development of osteonecrosis.

Peroneus longus and tibialis anterior muscle activity in the stance phase A quantified electromyographic study of 10 controls and 25 patients with chronic ankle instability

The electromyographic activity of the peroneus longus and anterior tibial muscles of 25 patients with chronic ankle instability (18 patients with bilateral symptoms and 7 patients with unilateral complaints) and 10 controls was registered during the stance phase under different walking conditions. With balance secured by external support, there was a variable amount of peroneal activity, most of which was found in the third quarter of stance. A high increase in peroneus longus activity starting after foot-flat was found when subjects had to maintain balance in a natural way. No difference in peroneal activity was found in relation to instability complaints. It is thought that the peroneus longus serves to maintain balance, that this function decreases with increase of speed and that one cannot rely on this muscle to prevent an inversion injury during normal walking. The anterior tibial muscle was predominantly active in the first quarter after heel contact. An increase in activity in the second quarter as an effect of loss of secured balance suggests that this muscle plays some part in balance control, but this is not its main function. A significant increase in tibialis anterior activity was found in patients with bilateral instability. No significant difference was found between the symptomatic and asymptomatic leg of patients with unilateral instability under the same walking conditions. These findings suggest changes in central control.

Medial Deviation of the First Metatarsal Head as a Result of Flexion Forces in Hallux Valgus

Several questions with regard to the hallux valgus complex, which includes metatarsus primus varus, give rise to discussion. How do bunions develop? Is disturbed muscle balance at the first metatarsophalangeal joint important in the pathogenesis of the hallux valgus complex? What is the relation between dynamic plantar load distribution and pain in the ball of the foot? What is the cause of recurrences of deformity after surgery? To answer these questions, we started with the bio-mechanical model of Snijders et al., 31 which states that contraction of flexor muscles of the hallux worsens its valgus angle and causes medial deviation of the first metatarsal head. The present study was designed to validate the model on patients. When pressing the hallux downward, simultaneously the force under the toe and the medial deviation of the first metatarsal head were measured on preoperative patients and on controls (35 subjects in all). We could demonstrate with statistical significance that (1) when the subjects with hallux valgus push the great toe on the ground, the first metatarsal head moved in medial direction; in other words the foot widened. In the controls, as an average, the foot became narrower. (2) The greater the valgus deviation of the hallux, the greater the effect of the toe flexors, and (3) the greater the valgus deviation of the hallux, the less maximal flexion force it can apply. Implications of these findings on conservative and surgical therapy are discussed. The recurrences of deformity after first metatarsal osteotomies are explained by the action of the hallux flexors. The stable result of arthrodesis of the first metatarsophalangeal joint is expected to be accompanied by narrowing of the foot as a result of contraction of the flexor muscles.

Weight bearing after arthrodesis of the first metatarsophalangeal joint: A randomized study of 61 cases

We performed a prospective randomized study of 61 cases of arthrodesis of the first metatarsophalangeal joint in 56 patients. In the first group, full weight bearing was allowed after 2-4 days and in the second group at 4 weeks. Radiographic union of the arthrodesis in the two groups did not differ.

Potential for Recurrence of Hallux Valgus after a Modified Hohmann Osteotomy: A Biomechanical Analysis:

On the basis of a biomechanical model the present study investigates whether a foot-widening effect, which may result in recurrence of bunions, can be demonstrated in operated patients. Therefore, the medial deviation of the first metatarsal head as a result of flexion forces on the hallux was measured in eight patients with clinical idiopathic hallux valgus, who underwent a modified Hohmann osteotomy, and in eight “normal” persons. We found that (1) before osteotomy, all forefeet broadened while pressing the big toe downward, and (2) after surgery, widening of the forefeet on average had significantly diminished, but still existed, which might explain the development of recurrences. (3) After surgery, the patients showed a slight, but statistically nonsignificant, decrease (from 37 N to 25 N) of the isometrically determined average maximal applicable flexion force. These abnormal hallux loads may cause, or result from, a deviation in gait pattern.

Failure of tibial bone grafting for femoral head necrosis

We treated 20 hips with femoral head necrosis in 16 patients using the Phemister tibial bone grafting procedure. After a mean follow-up of 3 years, the Harris hip score had improved in 15 out of 18 hips, however without radiographic improvement. In 2 hips, an arthrodesis and an arthroplasty were performed. We concluded that the aim of our treatment was not achieved.

Bilateral locked facets in the thoracic spine

Two cases of traumatic bilateral locked facets in the thoracic spine are reported. Both patients had only minor neurological signs. They both made a full neurological recovery after surgical reduction of the locked facets. Bilateral locked facets are very uncommon in the thoracic spine. The diagnosis should be considered in any patient with a fracture-dislocation of the thoracic spine. In these cases additional lateral tomographs are required. Early open reduction of bilateral locked facets and internal fixation are mandatory.

Reconstruction of the tibia by dual grafting : 3 cases of tumor resection

Large defects of the tibia can be bridged with autologous cancellous grafts between the remaining fibula and a contralateral tibial cortical graft. The long-term results of this technique in 3 cases after resection of a malignant tumor were either excellent or fair. It is concluded that this technique is an effective limb-saving surgical procedure.