A Field Study of Histologic and Bacteriologic Characterization of Femoral Head Separation and Femoral Head Necrosis.

Histologic and bacteriologic features for groups of average 31-day-old broilers displaying three gross categories of femoral head alterations were documented. Categories included simple femoral head separation (FHS), femoral head transitional changes (FHT), and femoral head necrosis (FHN). Groups with grossly normal (NORM) femoral heads and cull birds with FHN and having gross signs of sepsis (Cull-FHN) were also included in the study. There was a 10% occurrence of positive bacterial cultures for all birds tested. Most positive cultures (33%) were found in the Cull-FHN group, while only a 12% occurrence was seen in the FHS group, and no positives were present in the FHT or FHN groups. A 14% total occurrence of femoral bacterial chondronecrosis with osteomyelitis or simple osteomyelitis (BCO-O) was observed. A progressive increase in the prevalence of BCO-O was apparent between groups going from NORM (0%), FHS (4%), FHT (14%), FHN (13%), and reaching a maximum of 67% in the Cull-FHN group. Minimal to mild femoral head cartilage necrosis was present in 40% of NORM broilers and 100% of the FHS, FHT, and FHN groups, but at moderate severity in 20% of the Cull-FHN group. Thus, the majority of FHN cases were associated with aseptic cartilage necrosis rather than BCO-O. These findings suggest that aseptic cartilage necrosis may be as important as septic necrosis as a cause of gross femoral head disease. A 26% overall occurrence was seen for hip synovitis-arthritis, but group differences were not statistically significant. Synovitis was not seen in the NORM group and was present in some (12%) of the FHS group but was observed at a high rate in both the FHN (43%) and the Cull-FHN (50%) groups. Morphometric measurements demonstrated that the area size of femoral fibrous cortical defects or "cutback zones" were generally larger for all gross categories relative to NORM, with a significant difference between NORM and FHS groups. This study underscores the multifactorial etiology of FHN and the importance of conducting both histologic and bacteriologic evaluations in which gross evidence of FHN or BCO-O occurs.

Mycobacterium avium Complex Septic Arthritis Presenting as Osteonecrosis of the Femoral Head in a Patient With Systemic Lupus Erythematosus.

Mycobacterium avium complex is a rare cause of musculoskeletal infection, usually occurring in patients with compromised immune systems. Obtaining the diagnosis requires a high index of suspicion, and treatment can be delayed because of difficulty with isolating the organism. Treatment involves prolonged, targeted combination antibiotic therapy, and it is unclear whether eradication of the infection can occur in the presence of a foreign body, such as antibiotic spacers. The authors report a case of M avium infection presenting as presumed osteonecrosis of the femoral head in a young woman with systemic lupus erythematosus. She presented with collapse of her femoral head coinciding with several months of progressive, debilitating hip pain. She had mild fevers during that time, but results from multiple infectious workups, including hip aspiration, were negative. Purulent fluid was found in the operating room, but diagnosis was delayed for 5 weeks while waiting for cultures. The patient required 3 subsequent operations, eventually being left with a resection arthroplasty. Pertinent issues concerning diagnosis, therapy, and treatment challenges in M avium infections of the musculoskeletal system are discussed in this case report. [Orthopedics. 2017; 40(3):e549-e552.].

Viability of impacted bone allografts under metal mesh at the calcar in revision surgery of the hip.

Metal meshes are used in revision surgery of the hip to contain impacted bone grafts in cases with cortical or calcar defects in order to provide rotational stability to the stem. However, the viability of bone allografts under these metal meshes has been uncertain. We describe the histological appearances of biopsies obtained from impacted bone allografts to the calcar contained by a metal mesh in two femoral reconstructions which needed further surgery at 24 and 33 months after the revision procedure. A line of osteoid and viable new bone was observed on the surface of necrotic trabeculae. Active bone marrow between these trabeculae showed necrotic areas in some medullary spaces with reparative fibrous tissue and isolated reactive lymphocytes. This is interpreted as reparative changes after revascularisation of the cancellous allografts. These pathological findings are similar to those reported in allografts contained by cortical host bone and support the hypothesis that incorporation of morcellised bone under metal meshes is not affected by these devices.

An unusual case of hip septic arthritis due to Bacteroides fragilis in an alcoholic patient.

We describe a 53-year-old alcoholic man who presented with hip septic arthritis due to Bacteroides fragilis. This arthritis involved a severe destruction of the femoral head, which was completely devitalized. Recovery was achieved after 4 months of antimicrobial therapy with imipenem/cilastatin plus metronidazole, surgical debridement of the necrotic tissues and four sessions of hyperbaric oxygen.

Brucellosis induced avascular necrosis of the femoral head in a 7 year old child.

The case is reported of a 7 year old Bedouin girl who presented with a three week history of fever and limp. Initial tests for rheumatoid factor, antinuclear antibodies, and brucella were negative. Two weeks after admission Brucella melitensis was cultured from bone marrow and synovial fluid samples. The patient improved after treatment with doxycillin and streptomycin, but radiographs of the right hip showed avascular necrosis of the right femoral head. A mild limp and limitation of motion in the right hip persisted 18 months after admission.