Chris G. Sanford

Changes of pulmonary function for patients with osteoporotic vertebral compression fractures after kyphoplasty.

One of the consequences of osteoporotic vertebral compression fractures (OVCFs) is progressive collapse of the fractured osteoporotic vertebral body. This can lead to spinal kyphosis that may cause restriction of respiratory function. The balloon kyphoplasty procedure can reduce kyphosis and relieve the pain. There are few studies that have appropriate data and follow-up to evaluate the effect of deformity correction on pulmonary function after the kyphoplasty procedure. The current study explores changes of pulmonary function of 30 older women who suffered from OVCFs in the thoracolumbar segment after kyphoplasty. After kyphoplasty was performed on these women, thoracic kyphotic angle, local kyphotic angle, pain scores, and pulmonary function parameters—vital capacity, inspiratory capacity, residual volume, functional residual capacity, total lung capacity, forced vital capacity (FVC), and maximum voluntary ventilation (MVV) were measured. All measurements were taken before, 3 days after, and 1 month after the kyphoplasty. The height of the vertebral body was restored, the local kyphotic angle was improved, and pain scores were significantly decreased after kyphoplasty. FVC and MVV were significantly increased 3 days after the procedures; whereas only MVV had gone on to improve 1 month later. The decreased values of pain scores had a remarkably positive correlation with the percentage of improvement of FVC (r=0.536) and MVV (r=0.614) measured 3 days after kyphoplasty. In patients with OVCFs, kyphoplasty could partially improve their impaired lung function.

How the increase of the cervical disc space height affects the facet joint: an anatomy study.

Study Design. In vitro study on the effect of increasing the height of the cervical disc space on the facet joint. Objectives. To demonstrate how facet joint articulation is affected by increasing the cervical disc space height. Summary of Background Data. A surgeon attempts to increase the disc space and inserts a larger artificial disc than normal in order to keep the intervertebral foramen open and the prosthesis stable. However, it is hypothesized by the current authors that this procedure could have an adverse effect on the facet joints. Methods. Computerized tomography images passing through the disc space and the center of the C4–C7 facet joints (sagittal plane) were obtained from 15 cadaveric cervical spine specimens. A 1-mm incremental increase to a total 5 mm in disc space height was performed to simulate the changes seen in disc replacement. The change in the facet joint articulation overlap and space in the sagittal plane at normal and each displacement was measured. Results. Each 1-mm incremental increase in disc space at C4–C5 translated to a decrease in the facet joint articulation overlap in the sagittal plane by approximately 8%. The mean facet joint space increased approximately 0.8 mm. At the C5–C6 and the C6–C7 levels, the articulation overlap decreased by approximately 7% and the facet joint space increased approximately 0.8 mm. Conclusions. There is a significant decrease of the facet joint articulation overlap in the sagittal plane and an increase in the facet joint space following an increase in the cervical disc space. The inappropriate increase of the disc space height may result in facet joint subluxation and could lead to the accelerated failure of the artificial disc.

Systematic review of periprosthetic tibia fracture after total knee arthroplasties.

AIM To investigate the known incidences, treatment options, and related outcomes of periprosthetic tibia fractures after total knee arthroplasty (TKA). METHODS A literature search was done to identify studies that fit the inclusion criteria. The database search yielded 185 results, which were further reduced by the exclusion criteria to 13 papers, totaling 157 patients that met these criteria. Incidence rates of the different types of periprosthetic tibia fractures were determined and their treatments were subsequently analyzed based on the fractures subclass, with patient outcomes being overall favorable. RESULTS Of the 144 documented patients, 54 (37.5%) had a subclass C fracture, which are frequently seen in revision arthroplasties or when using cement intraoperatively. The fractures of subclasses A and B occur postoperatively. There were 90 subclass A and B fractures with incidences of 18.75% and 43.75% respectively. When broken down by type, 62 (55.36%) were type 1, 24 (21.4%) were type 2, 24 (21.4%) were type 3, and 2 (1.8%) were type 4. Furthermore, from the studies that included origin of injury, the types were further classified as having non-traumatic or traumatic origins. Type 1 had 78% (40/51) non-traumatic origin and 22% (11/51) traumatic origin. Fifteen fractures were type 2, but 5 were falls and 1 through a motor vehicle accident, giving a trauma causation of 40% (6/15). Of the 24 type 3 fractures, 12 were falls and 2 vehicular accidents, leading to a trauma causation of 58% (14/24). CONCLUSION Type 1 fractures were the most common. Subclass A was treated with locking plates, B required a revision TKA, and C was treated intraoperatively or nonoperatively.