Delayed Union of Stress Fracture of the First Rib in a Yoga Instructor: A Case Report.

CASE: We describe the case of a 38-year-old woman, a yoga instructor, who had pain in the right shoulder and scapular region of 4 months' duration while performing yoga. Radiography and computed tomography diagnosed delayed union of a first rib stress fracture. The delayed union of stress fracture of the first rib was successfully treated with the limiting of yoga activity and low-intensity pulsed ultrasound (LIPUS). CONCLUSIONS: Physicians should be aware that even yoga posing can cause stress fractures of the first rib. LIPUS therapy may be effective for delayed union in addition to rest.

Antibiotic-impregnated calcium phosphate cement as part of a comprehensive treatment for patients with established orthopaedic infection.

BACKGROUND: The treatment of established orthopaedic infection is challenging. While the main focus of treatment is wide surgical debridement, systemic and local antibiotic administration are important adjuvant therapies. Several reports have described the clinical use of antibiotic-impregnated calcium phosphate cement (CPC) to provide local antibiotic therapy for bone infections. However, these were all individual case reports, and no case series have been reported. We report a case series treated by a single surgeon using antibiotic-impregnated CPC as part of a comprehensive treatment plan in patients with established orthopaedic infection. METHODS: We enrolled 13 consecutive patients with osteomyelitis (n = 6) or infected non-union (n = 7). Implantation of antibiotic-impregnated CPC was performed to provide local antibiotic therapy as part of a comprehensive treatment plan that also included wide surgical debridement, systemic antibiotic therapy, and subsequent second-stage reconstruction surgery. We investigated the rate of successful infection eradication and systemic/local complications. The concentration of antibiotics in the surgical drainage fluids, blood, and recovered CPC (via elution into a phosphate-buffered saline bath) were measured. RESULTS: The mean follow-up period after surgery was 50.4 (range, 27-73) months. There were no cases of infection recurrence during follow-up. No systemic toxicity or local complications from the implantation of antibiotic-impregnated CPC were observed. The vancomycin concentration in the fluid from surgical drainage (n = 6) was 527.1 ± 363.9 µg/mL on postoperative day 1 and 224.5 ± 198.4 µg/mL on postoperative day 2. In patients who did not receive systemic vancomycin therapy (n = 3), the maximum serum vancomycin level was <0.8 µg/mL. In vitro vancomycin elution was observed from the CPC that was surgically retrieved (n = 2). CONCLUSIONS: Implantation of antibiotic-impregnated CPC is an option to provide local antibiotic therapy as part of a comprehensive treatment plan.

Backout of the helical blade of proximal femoral nail antirotation and accompanying fracture nonunion.

This article describes a case of backout of the helical blade, a rare complication of proximal femoral nail antirotation. A 31-year-old man had sustained a trochanteric fracture of his right femur. Fracture fixation using proximal femoral nail antirotation and autologous bone grafting 7 months later were performed at another hospital. However, bony union was not obtained, and the patient's pain and limp persisted. Therefore, he presented to the current authors. A radiograph taken at presentation revealed backout of the helical blade and fracture nonunion. A radiograph taken 1 month later showed a more advanced backout of the helical blade. The authors performed exchange nailing supplemented with transplantation of peripheral blood CD34-positive cells and autologous bone grafting. The proximal femoral nail antirotation was revised to a long gamma 3 nail, and a U-lag screw was used to obtain better stability. The postoperative course was uneventful. The patient regained ambulation without pain or support at 12 weeks postoperatively. Radiographic bony union was completed 9 months postoperatively. At 1-year follow-up, he could run and stand on the previously injured leg and had returned to work. Backout of the helical blade should be considered as a possible complication of proximal femoral nail antirotation. Incomplete fixation of the helical blade is the possible reason for backout. The use of a helical blade in young patients may cause difficulty in insertion and result in incomplete fixation.

Human hemarthrosis-derived progenitor cells can differentiate into osteoblast-like cells in vitro.

We hypothesized that intraarticular osteochondral fracture-induced hemarthrosis could be a useful cell source for bone regeneration, as it is thought to contain osteoprogenitor cells derived from bone marrow. Therefore, we investigated whether human hemarthrosis-derived cells have the potential to differentiate into osteoblast-like cells in vitro. We aspirated hemarthrosis from patients suffering from osteochondral fractures of knee joints, and cultured hemarthrosis-derived cells in a medium supplemented with dexamethasone, beta-glycerophosphate, and ascorbic acid, or without them as control. The morphology of the treated cells appeared to be cuboidal shape, differing from spindle-like shape observed in the control. Matrix mineralization was observed only in the treated culture. Alkaline phosphatase activity and gene expression of alkaline phosphatase, parathyroid hormone receptor, osteopontin, and osteocalcin were up-regulated compared with the control. These studies demonstrate that human hemarthrosis-derived cells can differentiate into osteoblast-like cells, i.e., they contain osteoprogenitor cells and are a useful cell source for bone regeneration.