Tag Archive | bone loss

Fracture Risk Rises after Gastric Bypass Surgery

Gastric Bypass for OBuzzThis post comes from Fred Nelson, MD, an orthopaedic surgeon in the Department of Orthopedics at Henry Ford Hospital and a clinical associate professor at Wayne State Medical School. Some of Dr. Nelson’s tips go out weekly to more than 3,000 members of the Orthopaedic Research Society (ORS), and all are distributed to more than 30 orthopaedic residency programs. Those not sent to the ORS are periodically reposted in OrthoBuzz with the permission of Dr. Nelson. 

Nearly 200,000 Americans have bariatric surgery each year, so it’s important to understand the long-term musculoskeletal consequences of those procedures. Gastric bypass constitutes the most common bariatric surgery and is believed to lead to bone loss. However, fracture risk in gastric-bypass patients has been insufficiently studied. Given that diabetes is an independent risk factor for fractures, any gastric bypass–fracture association should be studied in patients with and without diabetes.

That’s what Swedish researchers did in a retrospective cohort study1 of 38,971 obese patients who underwent gastric bypass—7,758 of whom had diabetes and 31,213 of whom did not. The patients in each of the two groups were propensity-score matched with controls (1 to 1). The researchers evaluated the overall risk of fracture and fall injury, along with fracture risk according to amount of weight loss and degree of calcium and vitamin D supplementation during the first year after surgery.

After a median follow-up of 3.1 years, gastric bypass was associated with an increased risk of any fracture, both in patients with diabetes (HR, 1.26) and without diabetes (HR, 1.32). Fracture risk appeared to increase with time. The risk of fall injury without fracture also increased after gastric bypass. (The increased risk of fall injury may explain some of the increased fracture risk.) Surprisingly, neither higher amounts of weight loss nor poor calcium and vitamin D supplementation during the first year after surgery were associated with increased fracture risk.

The metabolic consequences of surgically induced weight loss are significant for the obese population. Those consequences probably reach beyond bone to affect many aspects of musculoskeletal and possibly neurological homeostasis.

Reference

  1. Axelsson KF, Werling M, Eliasson B, Szabo E, Näslund I, Wedel H, Lundh D, Lorentzon M. Fracture Risk After Gastric Bypass Surgery: A Retrospective Cohort Study. J Bone Miner Res. 2018 Jul 16. doi: 10.1002/jbmr.3553. [Epub ahead of print] PMID: 30011091

Upcoming Own the Bone Events

ownbone_logo-r.pngSpring and Summer 2017 are busy seasons for Own the Bone, the American Orthopaedic Association’s national post-fracture, systems-based, multidisciplinary fragility fracture prevention initiative:

Webinar: Components of a Secondary Fracture Prevention Program – May 4

On Thursday, May 4, at 5:00pm CDT (6:00pm EDT) Paul A. Anderson, MD, FAOA, from the University of Wisconsin, and Karen Cummings, PA-C, from the University of Michigan, will discuss the components of a successful secondary fracture prevention program.

Own the Bone Charlotte SymposiumJune 23: Fragility Fracture Care Coordination and Secondary Fracture Prevention

Join the National Association of Orthopaedic Nurses (NAON) and The American Orthopaedic Association for this full-day event on Friday, June 23. Attendees will receive a Fragility Fracture Symposium Certificate of Completion and continuing education credit.

Fragility Fracture Workshop at PAOS Annual Conference – August 21, Baltimore, MD

Join Physician Assistants in Orthopaedic Surgery (PAOS) and Own the Bone for a full-day fragility fracture and bone health workshop on the first day of the PAOS Annual Conference, Monday, August 21, in Baltimore.

Including Osseous Fragment in Bankart Repair Yields Good Results

When treating shoulders with a Bankart lesion that includes an osseous fragment, many orthopaedic surgeons excise the fragment while repairing the capsulolabral complex, and then deploy one of various bone-augmentation procedures to address glenoid bone loss. But in the November 18, 2015 issue of JBJS, Kitayama et al. report on positive medium- to long-term results with a procedure that incorporates the osseous fragment into the Bankart repair and thus avoids invasive bone-grafting procedures.

Thirty-eight patients with a chronic osseous Bankart lesion and >15% bone loss of the inferior glenoid who underwent the procedure described by Kitayama et al. were available for follow-up after a mean of 6.2 years. One patient had a redislocation resulting from a traffic accident five months after surgery. But among the remaining patients, the mean Rowe score improved from 30.7 points preoperatively to 95.4 points postoperatively, and the mean WOSI index improved from 26.5% preoperatively to 81.5% postoperatively. Mean glenoid bone loss, measured two different ways using 3-D CT images, improved from 20.4% preoperatively to ‒1.1% postoperatively.

While the authors concede that “the exact time required for osseous union is not known,” they speculate that “if the repair survives without failure at least one year after surgery, a histological osseous union can be expected in the long postoperative period regardless of the amount of glenoid bone loss.” They attribute the normalization of the glenoid anatomy and low recurrence rate found in this study to “excellent fragment reduction and retensioning of the entire inferior glenohumeral ligament.”

JBJS Reviews Editor’s Choice–All About the Glenoid

The number of total shoulder arthroplasties performed in the United States has increased substantially in the past decade. In fact, since 2006, more total shoulder arthroplasties have been performed than hemiarthroplasties. Because of this surge in the number of total shoulder arthroplasties being performed, various techniques have been developed to address glenoid bone loss in patients with arthritic shoulder conditions. Indeed, primary glenoid bone loss usually occurs in association with osteoarthritis and is characterized by posterior wear patterns, whereas secondary glenoid bone loss usually occurs in association with trauma, glenoid loosening, and iatrogenic injury during revision surgery.

In the July 2015 issue of JBJS Reviews, Gowda et al. review a number of important issues related to this condition, including normal glenoid anatomy, pathological changes in glenoid substance, primary glenoid bone loss, proper imaging studies for the evaluation of the glenoid, principles of glenoid restoration, and the effects of poor implant position. Other topics, such as glenoid bone-grafting, the use of augmented components, glenoid insert design, patient-specific instrumentation, and the emergence of reverse total shoulder arthroplasty as an important component of the armamentarium of the shoulder arthroplasty surgeon, are also addressed.

The authors assert that proper preoperative imaging is critical in order to ascertain glenoid characteristics, including size, version, and depth of the vault. The treatment of glenoid bone loss is dependent on the degree of version correction that is required and consists of eccentric reaming, bone or polyethylene augmentation, and, as noted above, the potential use of reverse shoulder arthroplasty.

In the future, shoulder arthroplasty research should evaluate the long-term outcomes of biomaterial-augmented glenoid components, the use of other materials (such as ceramics), the utility of fixation within the glenoid and endosteal vault, and the use of reverse-polarity implants.

Thomas A. Einhorn, MD

Editor, JBJS Reviews