Bone Health

Lower extremity compartment syndrome When to suspect acute or chronic pressure buildup Randall Swain, MD; David Ross, MD VOL 105 / NO 3 / MARCH 1999 / POSTGRADUATE MEDICINE CME learning objectives To recognize both acute and chronic compartment syndromes in the sports setting To understand the differential diagnosis of lower leg pain in athletes To learn the workup and treatment of potential compartment syndrome cases

Review of post-op wound infections Nigerian Journal of Surgical Research 6(1-2)2004

Heterotopic Bone Formation/Ossification (HO)

Classification and management of nonunion of the humerus

Classification and management of tibial nonunion
definition: no evidence of healing over 3 months;
- FDA definition: frx that is over 9 months old and that has not shown radiographic signs of progression toward healing for 3 consecutive months;
- final stage of a nonunited fracture is formation of pseudoarthrosis;

Overview, classification and management of nonunion
frx of shaft of long bone should not be considered nonunion until at least 6 months post injury, esp treatment was complicated by infection;
- in contrast, a central fracture of the femoral neck can sometimes be defined as a non union after only 3 months;
- in established non union, sclerosis develops around the bone ends and medullary canals are sealed off;
- bone ends are joined by fibrous tissue;
- final stage of a nonunited fracture is formation of pseudoarthrosis

The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy
William H. Geerts, MD, FCCP; Graham F. Pineo, MD; John A. Heit, MD; David Bergqvist, MD, PhD; Michael R. Lassen, MD; Clifford W. Colwell, MD and Joel G. Ray, MD, MSc
Chest. 2004;126:338S-400S.
This article discusses the prevention of venous thromboembolism (VTE) and is part of the Seventh American College of Chest Physicians Conference on Antithrombotic and Thrombolytic Therapy: Evidence-Based Guidelines.

Wheeless' Textbook of Orthopaedics
“RSD” is an imprecisely used term; has been used to describe changes in soft tissue and bone;
- RSD may not involve the sympathetic nervous system and may not be the consequence of a reflex;
- 1995: IASP Consensus Conference: “Complex regional pain syndrome” replaced RSD
- CRPS Type 1: noxious event;
Type 2: nerve injury (causalgia)
- pain/hyperalgesia not limited to single nerve distribution, disproportionate to inciting event
- described as abnormal pain, swelling, vasomotor instability, contracture, and osteoporosis following injury or noxious stimulus.
- CRPS: other names - reflex sympathetic dystrophy, Sudeck’s atrophy, causalgia (minor and major), algodystrophy, shoulder-hand syndrome, post-traumatic pain syndrome, Painful post-traumatic osteoporosis, Transient migratory osteoporosis

A case of Total Hip Arthroplasty infection with Staphylococcus aureus co-infected with Salmonella choleraesuis was treated with two-stage exchange and administration of vancomycin and ciprofloxacin. No signs of re-infection have appeared 14 months after surgery. Cases of Salmonella infection of hip prostheses are quite rare, with only a handful of reports in the literature.

Wheeless Textbook of Orthopaedics Discussion: - most common complication in total hip arthroplasty and most common cause of component failure; - osteolysis is a time dependent process which arises from inflammatory reaction against polyethylene particulate debris; - patho-biology: - osteolysis is mediated primary by macrophages (fibroblasts and endothelial cells also play a role); - these cells are activated by wear debris (primarily polyethylene, but also metal and polymethylmethacrylate debris); - chemical mediators include: interleukin-1 (bone-resorbing cytokine) and tumor necrosis factor; - in the report by Yanming Bi et al (JBJS 2001), the authors present study showed that titanium particles induced both murine marrow cells and human peripheral blood monocytes to produce factors that stimulated osteoclast differentiation; - mean increase in osteoclast differentiation was 29.3 ± 9.4-fold. - they showed that titanium particles stimulate in vitro bone resorption primarily by inducing osteoclast differentiation;

eMedicine 2004 Patel
Synonyms and related keywords: tibial delayed union, aseptic nonunion, infected nonunion, tibial fractures, fractures of the tibia, nonunions of the tibia, broken leg, leg fracture, delayed healing, hypertrophic nonunions, atrophic nonunions, normotrophic nonunions, long bone fractures

Severe degenerative joint disease (DJD) of the knee results in pain, limited function, and a poorer quality of life. Total knee arthroplasty (TKA) is a safe and effective treatment of severe DJD of the knee. Patient satisfaction rates after TKA range from 90% to 95%.[1,2] The high satisfaction rate is dependent on the following factors: patient selection; implant design; surgical technique; and postoperative rehabilitation and compliance. However, TKA can fail, requiring that the patient undergo revision surgery. Annually, 35,000 TKAs are revised worldwide.[3] The published literature finds the following as the causes for failure of TKA: Infection; Loosening; Instability; Patellofemoral complications; Prosthesis fracture; and Polyethylene wear.[4-6] At The American Academy of Orthopaedic Surgeons 69th Annual Meeting, held in Dallas, Texas in February 2002, Dr. Peter F. Sharkey, from Philadelphia, Pennsylvania, and his colleagues[3] presented data describing the mechanisms of failure in a series of revision TKAs performed between September 1997 and October 2000. These investigators conducted a retrospective review of 212 consecutive TKAs in 203 patients who underwent total knee revision at the Rothman Institute in Philadelphia, Pennsylvania.