The evaluation of two methods for the placement of the tibial component of total knee arthroplasties in obese patients

Between December 2004 and October 2008 we studied 38 obese patients who underwent cemented total knee arthroplasty (using the rotating platform tibial tray) due to medial compartment osteoarthritis and consequent varus deformity. All patients had a body mass index (BMI)> 40. Functional outcome was assessed using the Knee Society Score (KSS). The study was based on the comparison between extramedullary (group A) and intramedullary (group B) instrumentation systems for the placement of the tibial prosthesis. The main endpoint was the immediate post-operative knee joint alignment.

There were 10 male and 28 female patients. The average follow-up period was 13.8 months (minimum follow-up of 6 months). There were 22 patients in group A whereas 16 patients comprised group B. In 5 of the 22 patients in group A there was an average varus malalignment of 40 and a mean KSS of 71.5 at the time of the latest follow-up visit. In the rest of patients of both groups there was a valgus alignment between 0 and 70 and a mean KSS of 86.4 respectively

Our experience suggests that the intramedullary instrumentation technique for the placement of the tibial component offers a more favourable post-operative alignment as well as better functional outcome in obese patients.

The timing of performing knee arthroplasties in bilateral osteoarthritic knees remains controversial. Our aim was to compare one-stage with two-stage bilateral knee arthroplasties (TKA).

Between November 2004 and April 2008, 128 patients (72 female and 56 male) underwent one-stage bilateral TKAs. Another group of 115 patients that underwent two-stage procedures during the same period formed the control group. All patients received the same type of anaesthesia. Study parameters included age, weight, medical co-morbidities, length of hospital stay, blood loss, post-operative complications and functional outcome.

There were no significant differences between the two groups. Co-morbidities and functional outcome based on the Knee Society Score were similar in both groups. In the one-stage group the length of hospital stay and blood losses were higher than the two-stage group; however less than double compared to the two-stage group. The early post-operative complications were higher but not statistically significant in the one-stage group.

Despite the fact that the early post-operative complications are slightly higher in the one-stage group, this particular method is an effective way of dealing with bilaterally osteoarthritic knees. It offers excellent functional outcome at a reduced cost

The evaluation of early results of combined percutaneous pedicle screw fixation and kyphoplasty for the management of thoraco-lumbar burst fractures

Between October 2008 and April 2009, 9 patients with thoracolumbar burst fractures underwent percutaneous short-segment pedicle screw fixation and augmentation kyphoplasty with calcium phosphate cement. All patients were selected according to the type of fracture (unstable type A3 fractures based on the Magerl classification) the absence of neurological signs and an intact posterior longitudinal ligament on the pre-operative MRI scan. Patient demographics, co-morbidities and complications were recorded. The main endpoints included Cobb angle correction, vertebral body height restoration and the length of hospital stay.

There were 3 male and 6 female patients with an average age of 43.6 years. The average follow-up was 2.4 months. The mean kyphotic angulation improved from 18.40 pre-operatively to 6, 80 post-operatively. The loss of vertebral body height improved from a mean of 38.7 % pre-operatively to 12.1 % post-operatively. The average duration of surgery was 40 minutes with insignificant blood loss. There were no post-operative complications. The average length of hospital stay was 3.2 days.

The combination of percutaneous short-segment pedicle screw fixation supplemented by balloon kypho-plasty for the management of thoracolumbar burst fractures with no neurological deficit offers correction of the normal thoracolumbar anatomy as well as augmentation of the anterior load-bearing column, using a minimally invasive technique. The early results are promising

The evaluation of results following posterior decompression and fusion for the management of cervical spondylotic myelopathy

Between July 2006 and May 2008, 68 patients with cervical myelopathy underwent posterior decompression with laminectomies and pedicle screw fixation of the cervical spine. All patients were selected based on the presence of multi-level degenerative disease and the correction of cervical lordosis on the pre-operative dynamic radiographs. Patient demographics, co-morbidities and post-operative complications were recorded and analysed. Functional outcome was assessed by using the Japanese Orthopaedic Association (JOA) score.

There were 37 male and 31 female patients with an average age 67.4 years. The average follow up period was 18 months. The mean pre-operative JOA score was 8.7, whereas the mean post-operative score was 12.1 on the latest follow-up visit. 9 patients had unsatisfactory clinical results and consequently underwent anterior procedures with significant improvement. Complications included 1 epidural haematoma, 2 superficial infections and 4 cases of myofascial pain. In three cases there was mild dysfunction of the C5 nerve root which resolved spontaneously with conservative measures.

In the present series of patients posterior decompression with laminectomies is an effective method for the management of cervical spondylotic myelopathy.

A 64-year-old man presented with a severe deformity of the tibia caused by Paget’s disease and osteoarthritis of the ipsilateral knee. Total knee replacement required preliminary correction of the tibial deformity. This was successfully achieved by tibial osteotomy followed by distraction osteogenesis using the Taylor spatial frame. The subsequent knee replacement was successful, with no recurrence of deformity.