Spinal instrumentation is a common method for the treatment of spinal disorders, but it can lead to the changes of spine biomechanics. Because of the stress changes, accelerated degeneration of the adjacent segment may occur as time goes by, namely adjacent segment disease. The accelerated degeneration can lead to secondary spinal stenosis, articulated joint degeneration, acquired spondylolisthesis, and spine instability, and some patients may have to receive surgery again. In recent years, the researchers gradually recognized the importance of this disease, and began to investigate its pathogenesis and management.
Humans ; Joint Instability ; etiology ; prevention & control ; Postoperative Complications ; diagnosis ; prevention & control ; Spinal Diseases ; surgery ; Spinal Fusion ; adverse effects ; instrumentation ; Spinal Stenosis ; etiology ; prevention & control ; Spondylolisthesis ; etiology ; prevention & control

OBJECTIVETo investigate the etiologies and prevention of patellar instability after total knee arthroplasty (TKA).

METHODSFrom September 1997 to April 2005, 94 patients (105 knees) underwent TKA without patellar resurfacing. All of them were osteoarthritis. Ten patients (14 knees) were performed with Rotation Knee (RK) prostheses. Forty patients were performed with mobile bearing TACK prostheses, and 44 patients with GEMINI prostheses. Subluxation and tilt of patella were evaluated by X-rays before or after operation.

RESULTSThe incidence of patellar instability after operation was 28.6% in patients who had genu valgus deformity, and was 29.5% in whom had patellar instability preoperative. The incidence of patellar instability in RK, TACK, and GEMINI group was 28.6%, 20.9%, and 16.7% respectively after operations. Four patients had obvious femoral or tibial components malrotation.

CONCLUSIONSThe etiologies of patellofemoral instability include pre-operative conditions, prosthetic design, and improper positioning of the prosthetic component. So the suitable component design and skillful operative technique will help the surgeon to avoid this complication.

Aged ; Arthroplasty, Replacement, Knee ; adverse effects ; methods ; Female ; Follow-Up Studies ; Humans ; Joint Instability ; etiology ; prevention & control ; Male ; Middle Aged ; Osteoarthritis, Knee ; surgery ; Patella ; Postoperative Complications ; etiology ; prevention & control

OBJECTIVETo investigate the results and indication of differently internal fixation for intertrochanteric fracture and prevent for complication.

METHODSOne hundred and two patients of intertrochanteric fracture of femur from January 1997 to December 2007 were reviewed and analysed. There were 46 males and 56 females, with an average age of 76.5 years ranging from 60 to 93 years. There were 34 cases of stability fractures and 68 of instability fractures. The methods of internal fixation included dynamic hip screw in 82 cases, proximal interlocking nail in 5, multi-screw fixation in 9, dynamic codylar screw in 6.

RESULTSThese patients were followed up for 6 to 72 months (36 months in average). The time of fracture healing was from 8 to 12 weeks. According to evaluation criterion of effect, the results were excellent in 72 cases, good in 20, fair in 10. After operation, there were 3 cases of coax vara, 2 cases of lag screws cutting out, 1 case of breakage of screw, 2 cases of avascular necrosis of the femoral head, 1 case of postoperative infection, 1 case of delayed union.

CONCLUSIONSuitable implant selection according the type of fracture, health condition is an important factor to reduce the incidence of complication for unstable fracture in aged patients. DHS is a main treatment of intertrochanteric fracture. PFN is recommended for serious osteoporosis or unstable intertrochanteric fracture. Compression screws is a choice for the fixation of type I and type II fracture of bad health condition.

Aged ; Aged, 80 and over ; Bone Screws ; Female ; Fracture Fixation, Internal ; methods ; Fracture Fixation, Intramedullary ; methods ; Fracture Healing ; physiology ; Hip Fractures ; complications ; surgery ; Humans ; Joint Instability ; physiopathology ; Male ; Middle Aged ; Postoperative Complications ; prevention & control

OBJECTIVETo discuss the reasons for the operation performed on 13 patients with upper cervical disease and to explore the management and prevention of upper cervical disease.

METHODSThirteen patients with upper cervical disease were retrospectively reviewed. The reason for of reoperations on these patients were analyzed. The measures to reduce upper cervical operational complication and bad prognosis were discussed to avoid reoperations.

RESULTSThe reasons for reoperations included 9 cases with unstable or re-dislocated atlantoaxial joint, 10 cases with residual spinal cord compression, 1 case with malposition of odontoid screw, 1 case with adjacent cervical spine regression, 1 case with occipital-cervical fusion failure, 1 case with spinal cord injury during operation, 1 case with bone-plant slipped into canales spinalis, and 1 case with demand to take out internal fixation for aggravated symptom.

CONCLUSIONSThe common reasons for upper cervical reoperations were due to instability or redislocation of atlantoaxial joint and residual of spinal cord compression. Some measures such as reducing operate miss, using firm internal fixation and decompressing were advisable to decrease the incidence of reoperations.

Adolescent ; Adult ; Atlanto-Axial Joint ; Cervical Vertebrae ; surgery ; Decompression, Surgical ; Female ; Humans ; Joint Instability ; etiology ; prevention & control ; surgery ; Male ; Middle Aged ; Postoperative Complications ; etiology ; prevention & control ; surgery ; Reoperation ; statistics & numerical data ; Spinal Cord Compression ; etiology ; prevention & control ; surgery ; Spinal Fusion ; Young Adult

The authors hypothesized that the placement of the interspinous implant would show a similar clinical outcome to the posterior lumbar interbody fusion (PLIF) in patients having spinal stenosis with mild segmental instability and that this method would be superior to PLIF without significantly affecting degeneration at the adjacent segments. Forty two adult patients having degenerative spinal stenosis with mild segmental instabilit who underwent implantation of Coflex(TM) (Spine motion, Germany) or PLIF at L4-5 between January 2000 and December 2003 were consecutively selected and studied for one-year clinical outcome. At 12 months after surgery, both groups showed a significant improvement in the visual analogue scale score and Oswestry disability index score for both lower extremity pain and low back pain. However, the range of motion at the upper adjacent segments (L3-4) increased significantly after surgery in the PLIF group, which was not manifested in the Coflex(TM) group during the follow-up. The authors assumed that interspinous implantation can be an alternative treatment for the spinal stenosis with segmental instability in selected conditions posing less stress on the superior adjacent level than PLIF.
Treatment Outcome ; Spinal Stenosis/complications/*surgery ; Spinal Fusion/*instrumentation/methods ; Prosthesis Design ; Pain Measurement ; Outcome Assessment (Health Care) ; Middle Aged ; Male ; Lumbar Vertebrae/*surgery ; Longitudinal Studies ; Joint Instability/complications/*prevention & control ; Intermittent Claudication/diagnosis/etiology/*prevention & control ; Humans ; Female ; Equipment Failure Analysis ; Back Pain/diagnosis/etiology/*prevention & control ; Aged ; Adult