The outcome of 260 repairs of the radial and posterior interosseous nerves, graded by Seddon’s modification of the Medical Research Council Special Committee’s system, was analysed according to four patterns of injury; open ‘tidy’, open ‘untidy’, closed traction, and those associated with injury to the axillary or brachial artery. We studied the effect on the outcome of delay in effecting repair and of the length of the defect in the nerve trunk. Of the 242 repairs of the radial nerve we found that 30% had good results and 28% fair; 42% of the repairs had failed. The violence of injury was the most important factor in determining the outcome. Of the open ‘tidy’ repairs, 79% achieved a good or fair result, and 36% of cases with arterial injury also reached this level. Most repairs failed when the defect in the nerve trunk exceeded 10 cm. When the repairs were carried out within 14 days of injury, 49% achieved a good result; only 28% of later repairs did so. All repairs undertaken after 12 months failed. Of the 18 repairs of the posterior interosseous nerve, 16 achieved a good result

We have reviewed 37 patients under the age of 18 years with lesions of the lumbar posterior end plate. All but one were active in sport, and most were seen because of low back pain. An abnormality was commonly found at the inferior rim of the body of L4 and at the superior rim of the sacrum. All adjacent intervertebral discs showed a decrease of signal intensity on the T2-weighted MRI. In 12 patients there was no interposed tissue at the posterior end-plate lesions. When disc material had migrated posteriorly none protruded beyond the posterior margin of the end plate, the dissociated portion of which was the main element compressing neural tissue. The posterior end-plate lesion should be regarded as a vertebral non-articular osteochondrosis

The posterior cruciate ligament (PCL) was imaged by MRI throughout flexion in neutral tibial rotation in six cadaver knees, which were also dissected, and in 20 unloaded and 13 loaded living (squatting) knees. The appearance of the ligament was the same in all three groups. In extension the ligament is curved concave-forwards. It is straight, fully out-to-length and approaching vertical from 60° to 120°, and curves convex-forwards over the roof of the intercondylar notch in full flexion. Throughout flexion the length of the ligament does not change, but the separations of its attachments do. We conclude that the PCL is not loaded in the unloaded cadaver knee and therefore, since its appearance in all three groups is the same, that it is also unloaded in the living knee during flexion. The posterior fibres may be an exception in hyperextension, probably being loaded either because of posterior femoral lift-off or because of the forward curvature of the PCL. These conclusions relate only to everyday life: none may be drawn with regard to more strenuous activities such as sport or in trauma

We have evaluated the functional, clinical and radiological outcome of patients with simple and complex acetabular fractures involving the posterior wall, and identified factors associated with an adverse outcome. We reviewed 128 patients treated operatively for a fracture involving the posterior wall of the acetabulum between 1982 and 1999. The Musculoskeletal Functional Assessment and Short-Form 36 scores, the presence of radiological arthritis and complications were assessed as a function of injury, treatment and clinical variables. The patients had profound functional deficits compared with the normal population. Anatomical reduction alone was not sufficient to restore function. The fracture pattern, marginal impaction and residual displacement of > 2 mm were associated with the development of arthritis, which related to poor function and the need for hip replacement. It may be appropriate to consider immediate total hip replacement for patients aged > 50 years with marginal impaction and comminution of the wall, since 7 of 13 (54%) of these required early hip replacement

1. A new operation of body-to-body intervertebral fusion by grafts introduced through a posterior approach is described. This is a preliminary report of early results, with follow-up to two years, which seems to be encouraging. 2. In spondylolisthesis, abnormal mobility of the loose posterior neural arch is believed in itself to cause nerve root pressure, and excision of the arch is an important part of the operation. 3. In the few cases where spinal fusion is needed after removal of a prolapsed intervertebral disc—and the proportion is now very low—posterior intervertebral fusion has proved very satisfactory

We have examined the relationship between the size of the flexion gap and the anterior translation of the tibia in flexion during implantation of a posterior cruciate ligament (PCL)-retaining BalanSys total knee replacement (TKR). In 91 knees, the flexion gap and anterior tibial translation were measured intra-operatively using a custom-made, flexible tensor-spacer device. The results showed that for each increase of 1 mm in the flexion gap in the tensed knee a mean anterior tibial translation of 1.25 mm (SD 0.79, 95% confidence interval 1.13 to 1.37) was produced. When implanting a PCL-retaining TKR the surgeon should be aware that the tibiofemoral contact point is related to the choice of thickness of the polyethylene insert. An additional thickness of polyethylene insert of 2 mm results in an approximate increase in tibial anterior translation of 2.5 mm while the flexed knee is distracted with a force of between 100 N and 200 N

From the experimental evidence above, it is clear that in the upper four centimetres of the forearm the posterior interosseous nerve moves up to one centimetre or more medially relative to the radius on pronation of the forearm. This movement becomes of importance when considered in relation to methods of operative approach for excision of the radial head. Operative approaches have been described in which emphasis has been placed on the position of incision, but in none of these is there any mention of the position of the forearm. We suggest that the following precautions should be taken. 1) During excision of the radial head the forearm should be kept in full pronation. 2) The incision should be as posterior as possible to ensure that it is well clear of the nerve. 3) With the forearm pronated the incision extends from a little above the lateral epicondyle along the postero-lateral aspect of the forearm for not more than 5 centimetres; proportionately less in a child. 4) The surgical assistant's attention should be brought to the damage that the posterior interosseous nerve might sustain from undue pressure–for instance by retraction, especially by bone levers–in the anterior part of the wound

The significance of the posterior cruciate ligament in the stability of the knee was investigated in dogs and it was compared with that of the anterior cruciate ligament by studying the changes produced in the knee after transection of either ligament. Osteophyte formation and changes in articular cartilage were less prominent after division of the posterior cruciate ligament. A complete longitudinal tear of the medial meniscus was found in eight out of the 10 dogs who had undergone section of the anterior cruciate but in none of the 10 with section of the posterior cruciate. It appears that, in dogs at least, the posterior cruciate ligament is less important than the anterior in the stability of the knee

The type II Monteggia (posterior) lesion is a rare injury which is sometimes associated with ulnohumeral instability. We have reviewed 23 of 28 patients with this injury. A clinical and radiographic assessment was undertaken at follow-up. Functional outcome scores, including the Broberg and Morrey Index and the Disabilities of the Arm, Shoulder or Hand (DASH), were used. The results from the six patients with associated posterior ulnohumeral dislocation were compared with 17 without ulnohumeral injury. Those with dislocation had reduced movement of the elbow and had outcome scores indicative of greater disability compared to those without associated dislocation

1. A case of spontaneous posterior interosseous paresis is reported. It is suggested that the cause was replacement fibrosis secondary to local ischaemic damage from unremembered minor trauma. 2. In a patient with a posterior interosseous nerve paresis examination may reveal a space-occupying lesion near the elbow along the course of the nerve thus compressing it. Recovery may be expected after its removal. Consequently the nerve should be explored before resort to tendon transfers

Aims

High-grade dysplastic spondylolisthesis is a disabling disorder for which many different operative techniques have been described. The aim of this study is to evaluate Scoliosis Research Society 22-item (SRS-22r) scores, global balance, and regional spino-pelvic alignment from two to 25 years after surgery for high-grade dysplastic spondylolisthesis using an all-posterior partial reduction, transfixation technique.

We have reviewed 38 surgically treated cases of spontaneous posterior interosseous nerve palsy in 38 patients with a mean age of 43 years (13 to 68) in order to identify clinical factors associated with its prognosis. Interfascicular neurolysis was performed at a mean of 13 months (1 to 187) after the onset of symptoms. The mean follow-up was 21 months (5.5 to 221). Medical Research Council muscle power of more than grade 4 was considered to be a good result. A further 12 cases in ten patients were treated conservatively and assessed similarly. Of the 30 cases treated surgically with available outcome data, the result of interfascicular neurolysis was significantly better in patients < 50 years old (younger group (18 nerves); good: 13 nerves (72%), poor: five nerves (28%)) than in cases > 50 years old (older group (12 nerves); good: one nerve (8%), poor: 11 nerves (92%)) (p < 0.001). A pre-operative period of less than seven months was also associated with a good result in the younger group (p = 0.01). The older group had a poor result regardless of the pre-operative delay. Our recommended therapeutic approach therefore is to perform interfascicular neurolysis if the patient is < 50 years of age, and the pre-operative delay is < seven months. If the patient is > 50 years of age with no sign of recovery for seven months, or in the younger group with a pre-operative delay of more than a year, we advise interfascicular neurolysis together with tendon transfer as the primary surgical procedure

We present the case of a 15-year-old boy with symptoms due to Klippel–Feil syndrome. Radiographs and CT scans demonstrated basilar impression, occipitalisation of C1 and fusion of C2/C3. MRI showed ventral compression of the medullocervical junction. Skull traction was undertaken pre-operatively to determine whether the basilar impression could be safely reduced. During traction, the C3/C4 junction migrated 12 mm caudally and spasticity resolved. Peri-operative skull-femoral traction enabled posterior occipitocervical fixation without decompression. Following surgery, cervical alignment was restored and spasticity remained absent. One year after surgery he was not limited in his activities. The surgical strategy for patients with basilar impression and congenital anomalies remains controversial. The anterior approach with decompression is often recommended for patients with ventral compression of the medullocervical region, but such procedures are technically demanding and carry a significant risk of complications. Our surgical strategy was an alternative solution. Prior to a posterior cervical fixation, without decompression, skull traction was used to confirm that the deformity was reducible and effective in resolving associated myelopathy

Posterior cervical wiring is commonly performed for patients with spinal instability, but has inherent risks. We report eight patients who had neurological deterioration after sublaminar or spinous process wiring of the cervical spine; four had complete injuries of the spinal cord, one had residual leg spasticity and three recovered after transient injuries. We found no relation between the degree of spinal canal encroachment and the severity of the spinal-cord injury, but in all cases neurological worsening appeared to have been caused by either sublaminar wiring or spinous process wiring which had been placed too far anteriorly. Sublaminar wiring has substantial risks and should be used only at atlantoaxial level, and then only after adequate reduction. Fluoroscopic guidance should be used when placing spinous process wires especially when the posterior spinal anatomy is abnormal

Seventy-two posterior psoas transfer operations performed in forty-four children with lumbar myelomeningocele were reviewed one to eight years after operation in an attempt to assess its value. Muscle charting, an objective recording of the child's walking ability, and radiographic examination of the hips were done. Hip stability was improved: 49 per cent were stable at the time of psoas transfer and 94 per cent at review. Functional results depended mainly on the level of neurological activity present: 57 per cent of the children had an acceptable functional result. Usually, posterior psoas transfer should be done as soon after the age of nine months as the child's condition will allow. Over the age of two years it should be restricted to children with activity in the third and fourth segments of the lumbar cord

A case of posterior fracture-dislocation of the shoulder is reported, and the method of closed reduction is described

Fusion is the main goal in the surgical management of the injured and unstable spine. A wide variety of implants is available to enhance this. Our study was performed to evaluate the stabilising characteristics of several anterior, posterior and combined systems of fixation. Six thoracolumbar (T11 to L2) spines from 13-week-old calves were first tested intact. Then the vertebral body of T13 was removed and the defect replaced and supported by a wooden block to simulate bone grafting. Dorsal implants consisting of a Universal Spine System (USS) fracture system and an AO Fixateur interne (AOFI), and ventral implants comprising of a Kaneda Classic, a Kaneda SR, a prototype of the VentroFix single clamp/single rod construct (SC/SR) and the VentroFix single clamp/double rod construct (SC/DR) were first implanted individually to stabilise the removal of the vertebral body. Simulating the combined anteroposterior stabilisations, all ventral implants were combined with the AOFI. The range of motion (ROM) was measured under loads of up to 7.5 Nm. The load was applied in a custom-made spine tester in the three primary directions while measuring the intervertebral movements using a goniometric linkage system. The dorsal systems limited ROM in flexion below 0.9° and in extension between 3.3° and 3.6° (median values). The improved Kaneda System SR yielded a mean ROM of 1.8° in flexion and in extension. The median rotation found with the VentroFix (SC/DR) was 3.2° for flexion and 2.8° for extension. Reinforcement of the ventral constructs with a dorsal system reduced the ROM in flexion and extension in all cases to 0.4° and lower. In rotation, the median ROM of the anterior systems ranged from 2.7° to 5.1° and for the posterior systems from 3.9° to 5.7°, while the combinations provided a ROM of 1.2° to 1.9°. In lateral bending, the posterior implants restricted movement to 1.1°, whereas the anterior implants allowed up to 5.2°. The combined systems provided the highest stability at less than 0.6°. Our study revealed distinct differences between posterior and anterior approaches in all primary directions. Also, different stabilisation characteristics were found within the anterior and posterior groups. Combinations of these two approaches provided the highest stability in all directions

1. Four out of five patients with spondylolisthesis, four-fifths of whom were seen at least five years after operation, had their symptoms relieved after posterior spinal fusion. 2. In a small series of patients treated by anterior spinal fusion, the results were less successful

Twenty-four children with infantile or juvenile idiopathic scoliosis had their spines corrected and solidly fused posteriorly before the age of eleven years. The growth of the fusion area was then accurately measured for a mean of 4.5 years during the adolescent growth spurt. During this period all longitudinal growth in the posterior elements ceased. The vertebral bodies continued to grow anteriorly, but the thick posterior fusion prevented the development of a lordosis. Initially the anterior growth was accommodated by narrowing of the intervertebral disc spaces, but eventually the vertebral bodies bulged laterally towards the convexity and pivoted on the posterior fusion, giving rise to loss of correction, increasing vertebral rotation and recurrence of the rib hump

1. Six patients suffering from spontaneous posterior interosseous paralysis are described. 2. Two were due to benign tumour and four due to traumatic neuritis, three of which were associated with minor hyperextension injuries to the elbow joint and one with long standing cubitus varus. 3. Surgical exploration was performed in each patient with recovery of nerve function