Introduction

Kinematics analyses of the spine have been recognized as an effective method for functional analysis of the spine. CT is suitable for obtaining bony geometry of the vertebrae but radiation is a clinical concern. MRI is noninvasive but it is difficult to detect bone edges especially at endplates and processes where soft tissues attach. Kinematics analyses require tracking of solid bodies; therefore, bony geometry is not always necessary for kinematics analysis of the spine. This study aimed to develop a reliable and robust method for kinematics analysis of the spine using an innovative MRI-based 3D bone-marrow model.

Study design: We conducted a prospective cohort study of 448 patients with a variety of spinal metastases.

Objective

To identify risk factors for the presence of distal adding-on in Lenke 1A scoliosis and compare different treatment strategies.

Introduction

How translation of different parts of spine responds to selective thoracic fusion has not been well investigated. Furthermore, how posterior pedicle-screw-only constructs affect spontaneous lumbar curve correction (SLCC) remains unknown. In a retrospective study, we aimed to investigate the balance change after selective thoracic fusion in Lenke 1C type adolescent idiopathic scoliosis (AIS) treated with posterior pedicle-screw-only constructs.

Introduction

Distal adding-on is often accompanied by unsatisfactory clinical outcome and high risk of reoperation. However, very few studies have focused on distal adding-on and its attendant risk factors, and optimum treatment strategies remain controversial. In a retrospective study, we aimed to identify risk factors for the presence of distal adding-on in Lenke 1A scoliosis and to compare different treatment strategies.

Introduction An international six-centre prospective observational cohort study.

Objective. To assess the feasibility of radical surgical excisional treatment of spinal metastasis

Materials and methods. Patients with histologically confirmed spinal metastasis originating from epithelial primary site mostly treated with instrumented surgery were studied. Surgical strategies were either radical excisional (enbloc and debulking) or palliative decompressive surgery. Outcomes assessed were measures of quality of life including pain, mobility, sphincter and neurological functions.

Results. A total of 223 patients with a mean age of 61 years and equal number of males and females were studied. Breast, renal, lung and prostate accounted for three quarters of tumours and 60% had metastasis that extended beyond one vertebra. Most patients presented with pain (92%), paraparesis (24%) and abnormal urinary sphincter 22% (5% were incontinent). Seventy four percent of patients underwent radical surgery, 92% of all patients had instrumented fixation. 73% of the radical group had improved pain control (63% for palliative group), 72% regained ability to walk (45% for palliative group), 92% maintained a functional neurological function of Frankel E/D (64% for palliative) and 55% had improved sphincter control (21% for palliative group).

Overall of all petients who underwent surgery, 71% had improved pain control, 53% regained mobility, 64% improved by at least one Frankel grade or maintained normal neurology and 39% regained normal urinary sphincter function. While 18% were bed bound preoperatively, only 5% were still in bed postoperatively. Perioperative mortality rate was 5.8% and morbidity was 21%. The median survival for the cohort was 352 days (11.7 months). The radical surgery group had a median survival of 438 days and the palliative group 112 days (P = 0.003).

Conclusion. Surgical treatment of spinal metastatic tumour is feasible with low mortality, an acceptably low morbidity and affords patients better quality of remaining life. Radical surgical excision has better outcome than palliative surgery in pain control and in neurological function rescue including regaining mobility and improvement in sphincter control.

Introduction: Spondylodiscitis is a rare but serious disease due to delay in diagnoses and inadequate treatment. The outcome mainly related to the early diagnosis.

The purpose of our study is to analyze retrospectively our patients, who had received conservative treatment or either posterior or combined approach.

Material and Method: Between 1992 and 2000, 163 patients were hospitalized due to spondylodiscitis; 62 were females and 101 males. The mean age was 56 years (1–83yrs).

The diagnosed was based on clinical examination, cultures, bone histology, X-rays, bone scan and MRI with gadolinium. The location of the infection was in 13 (8%) patients the cervical spine, in 62 (38%) the thorachic, in 10 (6%) the thoracolumbar junction and in 78 (48%) the lumbo-sacral spine. In 95 cases, concomitant diseases were present.

In 67 (41%) patients was not able to detect any microorganism. From the remaining patients, 53 (33%) were infected by staph.aureus and 22 (13%) by mycob tuberculosis.

The patients according to the treatment provided, were divided in three groups:

Group A: 70 patients, which had conservative treatment with antibiotics and bracing.

Results: The 12 months follow up reveals that 8 patients (11.4%) of group-A were operated. On the other hand 24 (42.9%) of the group-B were revised, as well as 6 (16.2%) patients from the group C.

The group A patients had not neurological symptoms. In group B, 11 had altered neurology and the operation was beneficial for 5 of them (45.5%), 4 remained unchanged and in 2 was deteriorate. In group C, 11 patients had altered neurology, from which 9 (81.8%) were improved and 2 remained unchanged.

The in-hospital complications were: 2 pulmonary embolism, 2 post operative haematomas, 1 persistent anaimia, 1 diafragm paralysis, 2 atelectasia and 1 cerebral thrombosis. In addition 3 patients had residual psoas abscess, 2 pancreas abscess, 1 cerebelum abscess and 3 lung infection.

The in-hospital mortality was 3 patients, other 17 patients died during the follow up

Conclusion: Spondylodiscitis is a valid diagnose for persisting back pain. Bacterial isolation is still difficult no matter the improved techniques, but in the majority of the cases is Staph.Aureus.

The conservative management in selected patients is effective up to 89%. From the operations performed the decompression alone had unacceptable high re-operation rate and also, it wasn’t so beneficial regarding the neurological improvement. If it is combined with anterior reconstruction and posterior stabilization provides better results.

We allocated randomly 27 patients undergoing 28 primary uncemented total hip replacements (THR) to receive prosthetic components of similar design with either plasma-sprayed titanium alloy (Ti) coating (n = 13) or hydroxyapatite (HA) coating (n = 15). After some exclusions, 15 of the patients (15 THR; 7 with HA- and 8 with Ti-coating) were followed by roentgen stereophotogrammetric analysis at 3, 6 and 12 months to measure migration of the femoral component. Twenty-six of the patients (26 THR) were followed clinically and by conventional radiography. All the femoral components had migrated at 3 months. From 3 to 12 months, the migration of Ti-coated components continued whereas the HA-coated components had stabilised. At 12 months there was significantly less migration of the HA-coated components (p < 0.05). The maximum subsidence was 0.2 mm in both groups. The Harris hip score was equal in the two groups preoperatively but at follow-up it was better in the HA-coated group (p < 0.05) and visual analogue scale scores showed that they had less pain (p < 0.05).

In previous studies, we have demonstrated a fibrocartilaginous membrane around hydroxyapatite-coated implants subjected to micromovement in contrast to the fibrous connective tissue which predominates around similarly loaded titanium alloy implants. In the present study, in mature dogs, we investigated the effect of immobilising titanium (Ti)- or hydroxyapatite (HA)-coated implants already surrounded by a movement-induced fibrous membrane and compared the results with those of similar implants in which continuous micromovement was allowed to continue. The implants were inserted in the medial femoral condyles of 14 dogs and subjected to 150 microns movements during each gait cycle. After four weeks (when a fibrous membrane had developed), half the implants were immobilised to prevent further micromovement. The dogs were killed at 16 weeks and the results were evaluated by push-out tests and histological analysis. The continuously loaded Ti-coated implants were surrounded by a fibrous membrane, whereas bridges of new bone anchored the HA-coated implants. The immobilised implants were surrounded by bone irrespective of the type of coating. Push-out tests of the continuously loaded implants showed better fixation of those with HA coating (p < 0.001). The immobilised Ti-coated implants had four times stronger fixation than did continuously loaded Ti-coated implants (p < 0.01) but there was no equivalent difference between the two groups of HA-coated implants. The amount of bone ingrowth was greater into immobilised HA-coated implants than into immobilised Ti-coated implants (p < 0.01). Two-thirds of the HA coating had been resorbed after 16 weeks of implantation, but 25% of this resorbed HA had been replaced by bone.(ABSTRACT TRUNCATED AT 250 WORDS)