Postoperative Gait Mechanics After Total Hip Arthroplasty: A Systematic Review and Meta-Analysis.

BACKGROUND: Total hip arthroplasty is recommended by clinical practice guidelines for improving pain in patients with severe hip osteoarthritis, yet functional limitations may persist postoperatively. The effects of the surgical approach on postoperative gait biomechanics may influence these limitations after total hip arthroplasty but are currently not well established. The purpose of this study was to investigate the differences in postoperative gait biomechanical differences, at early and late follow-up, in patients with hip osteoarthritis who underwent total hip arthroplasty using different surgical approaches. METHODS: Four electronic databases were searched from their inception to December 2016. Four pairs of reviewers independently determined study eligibility, rated study quality, and extracted data. Pooled estimates for each meta-analysis were obtained using a random-effects model. Mean differences (MDs) and standardized mean differences (SMDs) were calculated for spatiotemporal, kinematic, and kinetic gait variables at early (≤3 months) and late (≥6 months) postoperative follow-up. The posterior, anterior, direct lateral, and anterolateral approaches were compared using the mean postoperative differences between approaches, standard deviations, and sample sizes. RESULTS: Nineteen studies (757 participants) were included. Individual and pooled effect sizes for the differences between approaches were inconsistent, with minimal significant differences at early or late follow-up. A significant increase in step length was observed after the posterior approach compared with the anterolateral approach at early (SMD = 0.68, p = 0.035) and late (SMD = 0.46, p = 0.032) follow-up, as well as a significant increase in hip adduction moment after the posterior approach compared with the lateral approach at early follow-up (SMD = 0.70, p = 0.020). Effect sizes ranged from small to very large, but too few studies comparing similar surgical approaches, as well as inconsistent reporting of outcome measures, limited the ability to pool data. CONCLUSIONS: These findings suggest little early or late postoperative difference in gait biomechanics between surgical approaches. Although some significant differences between surgical approaches exist, determining whether the reported postoperative gait value differences are clinically meaningful remains a substantial challenge for the interpretation of these findings. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Does Balloon Kyphoplasty Deliver More Cement Safely into Osteoporotic Vertebrae with Compression Fractures Compared with Vertebroplasty? A Study in Vertebral Analogues.

Study Design A biomechanical and radiographic study using vertebral analogues. Objectives Kyphoplasty and vertebroplasty are widely used techniques to alleviate pain in fractures secondary to osteoporosis. However, cement leakage toward vital structures like the spinal cord can be a major source of morbidity and even mortality. We define safe cement injection as the volume of the cement injected into a vertebra before the cement leakage occurs. Our objective is to compare the amount of cement that can be safely injected into an osteoporotic vertebra with simulated compression fracture using either vertebroplasty or balloon kyphoplasty techniques. Methods Forty artificial vertebral analogues made of polyurethane with osteoporotic cancellous matrix representing the L3 vertebrae were used for this study and were divided into four groups of 10 vertebrae each. The four groups tested were: low-viscosity cement injected using vertebroplasty, high-viscosity cement injected using vertebroplasty, low-viscosity cement injected using balloon kyphoplasty, and high-viscosity cement injected using balloon kyphoplasty. The procedures were performed under fluoroscopic guidance. The injection was stopped when the cement started protruding from the created vascular channel in the osteoporotic vertebral fracture model. The main outcome measured was the volume of the cement injected safely into a vertebra before leakage through the posterior vascular channel. Results The highest volume of the cement injected was in the vertebroplasty group using high-viscosity cement, which was almost twice the injected volume in the other three groups. One-way analysis of variance comparing the four groups showed a statistically significant difference (p < 0.005). Conclusions High-viscosity cement injected using vertebroplasty delivers more cement volume before cement leakage and fills the vertebral body more uniformly when compared with balloon kyphoplasty in osteoporotic vertebrae with compression fractures.

Rickets and osteomalacia in Saudi children and adolescents attending endocrine clinic, Riyadh, Saudi Arabia.

This is a retrospective study in which we report our clinical experience during the period from January 1990 to December 2009, from a paediatric endocrine clinic at King Khalid University Hospital (KKUH), Riyadh, Saudi Arabia. The diagnosis of rickets and oestomalacia was based on clinical, biochemical and radiological data. Eighty-one (34 males and 47 females) children and adolescents with rickets or osteomalacia aged 2 to 18 years (mean; 9.5 years) were evaluated. The commonest causes were nutritional; either low Vitamin D or calcium, or both. In 58 (71.60%) patients, eight patients (9.87%) were due to chronic use of anticonvulsant medications, while five (6.17%) patients were diagnosed to have celiac disease. Non-specific symptoms, such as bone pain and fatigue were the most common presenting symptoms which may indicate that other cases were possibly missed. Lack of direct sun exposure and malnutritional practices were evident. Several genetically inherited disorders were diagnosed; including; hypophosphataemic rickets in three (3.70%), vitamin D-dependent-rickets type 2 in five (6.17%) and pseudohypo-hyperparathyroidism in one (1.23%) child. Rickets was secondary to chronic renal failure in only one patient (1.23%). In conclusion, a diversity of disorders caused rickets or osteomalacia in our series. Paediatricians should be familiar with such different types and able to differentiate them from disorders mimicking rickets. rickets, such as hypophosphatasia, and metaphyseal dysplasias. An active plan should be put in place to prevent rickets and osteomalacia among young age groups.