Objectives. Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. Materials and Methods. A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm. 3. (standard deviation (. sd). 52). The anterior pelvic ring fracture was fixed with either one 7.3 mm cannulated screw (Group 1) or two 3.5 mm pelvic cortex screws (Group 2). Progressively increasing cyclic axial loading was applied through the acetabulum. Relative movements in terms of interfragmentary displacement and gap angle at the fracture site were evaluated by means of optical movement tracking. The Wilcoxon signed-rank test was applied to identify significant differences between the groups. Results. Initial axial construct stiffness was not significantly different between the groups (p = 0.463). Interfragmentary displacement and gap angle at the fracture site were also not statistically significantly different between the groups throughout the evaluated cycles (p ⩾ 0.249). Similarly, cycles to failure were not statistically different between Group 1 (8438, . sd. 6968) and Group 2 (10 213, . sd. 10 334), p = 0.379. Failure mode in both groups was characterised by screw cutting through the cancellous bone. Conclusion. From a biomechanical point of view, pubic ramus stabilisation with either one large or two small fragment screw osteosynthesis is comparable in osteoporotic bone. However, the two-screw fixation technique is less demanding as the smaller screws deflect at the cortical margins. Cite this article: Y. P. Acklin, I. Zderic, S. Grechenig, R. G. Richards, P. Schmitz, B. Gueorguiev. Are two retrograde 3.5 mm screws superior to one 7.3 mm screw for anterior pelvic ring fixation in bones with low bone mineral density? Bone Joint Res 2017;6:8–13. DOI: 10.1302/2046-3758.61.BJR-2016-0261

Seven men with a mean age of 63.9 years (59 to 67) developed dysphagia because of oesophageal compression with ossification of the anterior longitudinal ligament (OALL) and radiculomyelopathy due to associated stenosis of the cervical spine. The diagnosis of OALL was made by plain lateral radiography and classified into three types; segmental, continuous and mixed. Five patients had associated OALL in the thoracic and lumbar spine without ossification of the ligamentum flavum. All underwent removal of the OALL and six had simultaneous decompression by removal of ossification of the posterior longitudinal ligament or a bony spur. All had improvement of their dysphagia. Because symptomatic OALL may be associated with spinal stenosis, precise neurological examination is critical. A simultaneous microsurgical operation for patients with OALL and spinal stenosis gives good results without serious complications

Over the past 19 years we have operated on 269 patients with myelopathy associated with cervical spondylosis. We report our results in 191 cases which we have followed up for 1 to 12 years (average 31 months). The clinical state before and after operation was recorded using the criteria of the Japanese Orthopaedic Association. Posterior operations gave better results than anterior for the more advanced myelopathies such as transverse lesions, the Brown-Sequard syndrome and the motor syndromes, but the brachialgia and cord syndrome and the central cord syndrome were satisfactorily treated by anterior operations. Of the three anterior and three posterior techniques used, no single one showed an overall superiority. A short duration of symptoms before operation was associated with better results, but these were not influenced by the age of the patients

Objectives. To evaluate the applicability of MRI for the quantitative assessment of anterior talofibular ligaments (ATFLs) in symptomatic chronic ankle instability (CAI). Methods. Between 1997 and 2010, 39 patients with symptomatic CAI underwent surgical treatment (22 male, 17 female, mean age 25.4 years (15 to 40)). In all patients, the maximum diameters of the ATFLs were measured on pre-operative T2-weighted MR images in planes parallel to the path of the ATFL. They were classified into three groups based on a previously published method with modifications: ‘normal’, diameter = 1.0 - 3.2 mm; ‘thickened’, diameter > 3.2 mm; ‘thin or absent’, diameter < 1.0 mm. Stress radiography was performed with the maximum manual force in inversion under general anaesthesia immediately prior to surgery. In surgery, ATFLs were macroscopically divided into two categories: ‘thickened’, an obvious thickened ligament and ‘thin or absent’. The imaging results were compared with the macroscopic results that are considered to be of a gold standard. Results. Agreement was reached when comparison was made between groups, based on MRI and macroscopic findings. ATFLs were abnormal in all 39 cases and classified as ten ‘thickened’ and 29 ‘thin or absent’. As to talar tilt stress radiography, a clear cut-off angle, which would allow discrimination between ‘thickened’ and ‘thin or absent’ patients, was not identified. Conclusion. MRI is valuable as a pre-operative assessment tool that can provide the quantitative information of ATFLs in patients with CAI. Cite this article Bone Joint Res 2014;3:241–5

Subtalar dislocation is a significant injury characterised by late complications, including subtalar arthritis. We describe a rare case of irreducible posterior subtalar dislocation due to incarceration of a fracture of the anterior process of the calcaneum in the subtalar joint, and discuss appropriate management

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

An isolated palsy of the anterior interosseous nerve of the forearm is described in a boy aged nine. It was cured by surgical division of a constricting fibrous band in the forearm

We have investigated the anatomy of the proximal part of the ulna to assess its influence on the use of plates in the management of fractures at this site. We examined 54 specimens from cadavers. The mean varus angulation in the proximal third was 17.5° (11° to 23°) and the mean anterior deviation 4.5° (1° to 14°). These variations must be considered when applying plates to the dorsal surface of the ulna for Monteggia-type fractures. A pre-operative radiograph of the contralateral elbow may also be of value

Postoperative anterior knee pain was evaluated in a consecutive series of 138 knees in 108 patients with rheumatoid arthritis treated by total knee replacement with Mark I Insall-Burstein prostheses. No knee had primary patellar resurfacing, and in the 119 knees followed up for a mean of 63.9 months, none had secondary resurfacing. Anterior knee pain was absent in 87 knees (73%), mild in 16 (13.5%) and moderate or severe in 16 (13.5%). The height of the patella above the prosthetic joint line was the only variable which was directly related to the incidence of anterior knee pain. The sensitivity and specificity of patellar height measurements for identifying patients with or without pain were derived. From these data, a selective policy of resurfacing the patella in those at risk was adopted. Choosing a patellar height of 15 mm or less, patellar resurfacing could be avoided in 80% of patients likely to have no pain, and the patella could be resurfaced in 65% of those likely to have anterior knee pain

1. Un reduced anterior dislocation of the hip is very uncommon. Four cases are reported. 2. The aim of treatment is to correct the deformity, to improve the gait and to produce pelvic stability. 3. Osteotomy of the femur at the trochanteric level is the simplest corrective operation and will greatly improve the function of the limb

1. Seven cases of old unreduced anterior dislocation of the hip are reported. Six were complicated by myositis ossificans. 2. Four cases resulted from the fall of a heavy object on the lower back of a stooping person. 3. Trochanteric osteotomy in five cases not only corrected the deformity but gave stable, serviceable hips

Three cases of isolated anterior dislocation in the proximal tibiofibular joint are presented. The common aetiological feature was that injury occurred with the knee in hyperflexion and the foot inverted and extended. The symptoms of locking, pain and giving way may lead to an erroneous diagnosis of meniscal injury. Early diagnosis in the acute case enabled easy reduction. In the inveterate cases, resection of the head of the fibula gave complete relief of symptoms

We have reviewed 36 patients who had recurrent anterior dislocation of the shoulder after a previous anterior repair and analysed the various causes of failure. It was found that failure could have been avoided in virtually all of the patients by correct pre-operative diagnosis, selection of the appropriate operation and its proper execution. The further management of these patients is described and suggestions are made as to means of reducing the incidence of failure after primary operation

Lesions of the anterior interosseous nerve in the forearm are rare and often misdiagnosed as tendon injuries. A consecutive series of 13 patients with this condition referred for electrodiagnosis is reviewed. Only three had originally a correct clinical diagnosis and three were initially considered to have tendon ruptures. Five cases were of mechanical origin and seven due to ‘neuritis’. All showed electrophysiological abnormalities, most commonly involving the pronator quadratus. Late spontaneous recovery was common, and only one case had surgical exploration

A study of the attachment of the joint capsule to the scapula, and of the shape of the humeral head, has been carried out in 52 fetal and embryonic shoulders. In 77% of cases the anterior capsule was attached to the labrum or close to it; in the remaining 23% it was inserted into the neck of the scapula, so creating a pouch. In all 52 specimens the humeral head was spherical. It was concluded that the pouched and redundant anterior capsule sometimes seen during surgery for recurrent dislocation of the shoulder, may not be traumatic in origin, but could be a developmental variant

We have reviewed 10 patients treated for anterior tarsal tunnel syndrome produced by compression of the deep peroneal nerve or its branches, and we have studied the anatomy of the tunnel in 25 adult feet. The causes of onset of the syndrome included contusion of the dorsum of the foot, tight shoe laces, talonavicular osteophytosis, ganglion, and pes cavus. The clinical signs were often diagnostic but electromyography was helpful. Operative decompression in nine feet of eight patients gave successful results at 1.5 to 4 years follow-up

Out of a total of 623 patients who, over a ten-year period, underwent primary total knee replacement (TKR) without patellar resurfacing, 20 underwent secondary resurfacing for chronic anterior knee pain. They were evaluated pre- and postoperatively using the clinical and radiological American Knee Society score. The mean follow-up was 36.1 months (12 to 104). The mean knee score improved from 46.7 to 62.2 points and the mean functional score from 44.7 to 52.2 points. Only 44.4% of the patients, however, reported some improvement; the remainder reported no change or deterioration. The radiographic alignment of the TKR did not influence the outcome of secondary resurfacing of the patella. Complications were noted in six of the 20 patients including fracture and instability of the patella and loss of movement. Anterior knee pain after TKR remains difficult to manage. Secondary resurfacing of the patella is not advocated in all patients since it may increase patient dissatisfaction and hasten revision

1. A series of experiments on the tensile strength of the anterior capsular mechanism have been performed. These show that in the young the weakest point is the glenoid labral attachment, whereas in the elderly calcification of tissues makes the capsule and subscapular tendon weaker. 2. It has been shown previously that glenoid labral detachment is the common injury in the young at the time of an acute dislocation, whereas capsular rupture and subscapularis tendon damage occur in the elderly. 3. These findings suggest that in an acute anterior dislocation of the shoulder the shoulder integuments give at their weakest point, and that it is the site of this weakest point and not the mechanism of injury which influences the liability to recurrence

Thirteen patients with dystrophic spinal deformities from neurofibromatosis treated by anterior and posterior fusion have been reviewed. The shortest follow-up was five years, the average seven years. Combined fusion produced satisfactory results in patients with a smooth kyphoscoliosis or with scoliosis without kyphosis, but it was unsatisfactory in patients with an angular kyphoscoliosis. Of the five patients with angular kyphoscoliosis, one had a persistent pseudarthrosis after operation and all had progression of the kyphosis despite the treatment. The morbidity rate also was high in this group of patients. Many of the complications were related to soft-tissue manifestations of the disease. It is recommended that very special attention be paid to the dystrophic angular deformity in neurofibromatosis; even anterior and posterior spinal fusion may fail to control its progression

We report the results of anterior soft-tissue release of the hip for fixed flexion deformity in 17 patients (31 hips) with juvenile chronic arthritis. The mean age at operation was 8 years 6 months. All the patients were reviewed at one and three years and 11 (21 hips) were available for review at five years. The results were good as regards early pain relief and improved mobility. At one year, the average fixed flexion deformity was reduced from 35 degrees to 9.5 degrees, and at three years it was 18 degrees. This degree of improvement was maintained in the hips followed for five years. At 5 to 12 years' follow-up (mean 6.7) seven patients (14 hips) have required no further surgery and have maintained an acceptable range of motion. We discuss the influence of surgery on radiographic changes and on femoral neck anteversion