The in vivo evaluation of patellofemoral contact pressures in a posterior stabilized compared to posterior cruciate sacrificing total knee arthroplasty (TKA). A prospective descriptive non randomized study was performed on 8 patients. A standard approach to a TKA was performed using a balanced gap technique, while the patella was prepared for a resurfacing. The trial components for the posterior stabilized (PS) TKA where inserted including the gas sterilized pressure transducer (a patella button). Soft tissue was approximated and the knee was taken through full range of movement. Patellofemoral pressure was measured and captured continuously through the full range of movement. The posterior cruciate sacrificing (CS) components were inserted into the same patient and the procedure repeated. In addition, anterior translation of the tibia relative to the femur was measured at 90 degrees. The transducer was removed and final components, including a patella resurfacing were inserted.Purpose Of Study
Methods
The aim is to assess the use of non-fusion instrumentation “growth rods” in early onset scoliosis (EOS). A retrospective review of 12 consecutive patients who had undergone a growth rod procedure for EOS was performed. Six patients had neuromuscular scoliosis, 5 had juvenile idiopathic scoliosis while one had a congenital aetiology. Growth constructs were predominately constructed from modular commercially available sets using hooks, screws and connection blocks. One VEPTR was used in a severe kyphoscoliosis. Patients returned to theatre at 6 monthly intervals for a lengthening procedure. Patients were assessed with regards to age at presentation, age at surgery, indications for surgery, initial Cobb angle, post- operative Cobb angle, number of lengthening's done, instrumentation used, amount of spine growth achieved and complications.Purpose of study
Methods
Neck pain can be caused by pressure on the spinal cord or nerve roots from bone or disc impingement. This can be treated by surgically decompressing the cervical spine, which involves excising the bone or disc that is impinging on the nerves or widening the spinal canal or neural foramen. Conventional practise is to fuse the adjacent intervertebral joint after surgery to prevent intervertebral motion and subsequent recompression of the spinal cord or nerve root. However fusion procedures cause physiological stress transfer to adjacent segments which may cause Adjacent Segment Degeneration (ASD), a rapid degeneration of the adjacent discs due to increased stress. ASD is more likely to occur in fusions of two or more levels than single level fusions and is more common where there is existing degeneration of the adjacent discs, which is not unusual in people over 30 years of age. Partial dynamic stabilisation, which generally involves a semi-rigid spinal fixation, allows a controlled amount of intervertebral motion (less than physiological, but more than fusion) to prevent increased stress on the adjacent segments (potentially preventing ASD) whilst still preventing neural recompression. Partial dynamic stabilisation is suitable for treating spinal instability after decompression as well as certain degenerative instabilities and chronic pain syndromes. Dynamic stabilisation and semi-rigid fixation systems for the spine are typically fixated posteriorly. However, choice of posterior surgical stabilisation techniques in the cervical spine is limited due to the size of the osseous material available for fixation and the close proximity of the neural structures and the vertebral artery. Posterior dynamic stabilisation systems for stabilisation of the lumbar spine often use the pedicle as an anchor point. Using the pedicle of the cervical spine as an anchor point is technically difficult because of its small size, angulation and proximity to neurovascular structures. Therefore, one of the main challenges to provide stabilisation in the cervical spine is the limitations of the anatomy. This presentation will introduce a novel spinal implant (patent pending) which is proposed for the cervical spine to provide partial dynamic stabilisation in the C3 to T1 region from a posterior approach. The implant is a single unit with a safe and technically simple insertion technique into the lateral masses. The implant uses a simple mechanism to allow limited intervertebral motion at each instrumented level. It is hoped that the simplicity of the device and removing the need to provide a bone graft anteriorly may reduce the cost of the procedure compared to traditional fusion and competing surgeries.
Fast bowling in the game of cricket requires repetitive spinal extension, lateral deviation, lumbar flexion and thoracodorsal rotation. Back pain is common, and it has been shown that pars interarticularis defects had occurred in over 50% of a group of teenage fast bowlers. Many of these defects will heal, but some cause chronic pain which prevents bowling, although other activities may be painless. We report the successful results of local screw fusion of the pars interarticularis defects in ten bowlers, and recommend this method for this small group of sportsmen.
The action of fast bowling in the game of cricket is known to cause injuries to the lumbar spine. We studied a group of 16- to 18-year-old fast bowlers, selected for special training in Western Australia. All 24 had MR scans of the spine, 22 had radiographs and CT scans; in 20 the bowling technique was analysed biomechanically. There was a high incidence of back pain and this was always associated with a radiological abnormality. Pars interarticularis defects were diagnosed in 54% and intervertebral disc degeneration in 63%. Bowling actions which involved counter-rotation were associated with a higher incidence of both injuries.
Trendelenburg's test of function of the hip joint was first reported before radiology was available. At least four methods of performing it have since been described in the literature. We examined 50 normal subjects and 103 people with disorders affecting either the spine or the hip, in order to determine the different responses that occurred when they were asked to stand on one leg. This has enabled us to define a standard method of performing the Trendelenburg test, and to interpret the test as a method of assessing hip abductor function. The major pitfalls that result in misinterpretation, or false-positive responses, are pain, lack of cooperation from the patient, and impingement between the rib cage and the iliac crest. False-negative responses result from the patient using muscles above and below the pelvis, and from leaning beyond the hip on the standing side.
One hundred patients with acute ruptures of the lateral ligaments of the ankle were randomly allocated either to conservative treatment in a plaster cast or to operative repair. With the aid of stress tenography, the extent of the injury was established. There were 30 patients with isolated anterior talofibular ruptures and 20 with additional calcaneofibular ligament ruptures in each treatment group. Operative repair was associated with a higher incidence of complications in the first weeks, and slightly delayed the patients' return to work. At an independent two-year review there was no evidence that operative repair offered improved symptomatic or functional benefit.
Injuries to the tarsometatarsal (Lisfranc) joint are not common, and the results of treatment are often unsatisfactory. Since no individual is likely to see many such injuries, we decided to make a retrospective study of patients from five different centres. In this way 119 patients with injuries of the Lisfranc joint have been collected. This paper classifies these injuries and describes their incidence, mechanism of production, methods of treatment, results and complications. Sixty-nine of the patients attended for review: 35 of these had been treated by closed methods, 27 had had an open reduction and seven patients had had no treatment. On the basis of our study we suggest that these injuries should be classified according to the type of injury rather than the nature of the deforming force and that their treatment be based upon this classification. It seems that, whatever the severity of the initial injury, prognosis depends on accurate reduction and its maintenance.
A study was undertaken to assess the degree of inter-observer error when a panel of observers classified the radiographs of patients with early Perthes' disease, using Catterall grouping and "at risk" signs. The anteroposterior and lateral radiographs, taken within three months of diagnosis of Perthes' disease, were available for 69 hips and were shown in turn to 10 observers. The radiological end-results were assessed at least four years from diagnosis. The results showed a poor ability of the observers to delineate Groups 1, 2 and 3, with a more satisfactory performance in Group 4 and when Groups 2 and 3 were combined. Interpretation of "at risk" signs was unsatisfactory except when there was an increase in medial joint space greater than two millimetres. The end-results correlated well with early Catterall grouping and "at risk" signs when these were correctly interpreted.
