Reinfection rates after one- and two-stage revision surgery for hip and knee arthroplasty: a systematic review and meta-analysis.

PURPOSE: Revisions for periprosthetic joint infection of knee and hip arthroplasty can be performed following one- or two-stage treatment protocols. Current literature is inconclusive whether one protocol is superior to the other, as prior literature reported similar reinfection rates for both treatment options. We aimed to provide a systematic review and meta-analysis of current literature on septic arthroplasty revisions. METHODS: Between April 2015 and December 2020, Medline, Embase, and The Cochrane Library were searched for studies reporting reinfection outcomes in patients treated with one-stage and two-stage knee or hip revision arthroplasty. Two reviewers independently extracted data and disagreements were resolved by a third investigator. We utilized a double arcsine transformation, prior to pooling using a random-effects model. RESULTS: For hip revision arthroplasty, we identified 14 one-stage studies (n = 1237) with a pooled reinfection rate of 5.7% (95% CI 3.7-8.1%), and 46 two-stage studies (n = 5009) with a reinfection rate of 8.4% (95% CI 6.9-9.9%). For knee revision arthroplasty, 6 one-stage studies (n = 527) and 48 two-stage studies (n = 4344) were identified with reinfection rates of 12.7% (7.0-19.7%) and 16.2% (13.7-19.0%), respectively. Overall, reinfection rates did not vary substantially after subgroup analysis. Limitations of our study are the limited amount of one-stage studies that introduce a potential bias. CONCLUSION: The reinfection rates following one- and two-stage hip and knee arthroplasty revisions were similar. Knee reinfection rates have increased compared to the previous analysis. Individual patient characteristics and adequate treatment algorithms are needed for a more individual selection approach, until a randomized trial is performed.

Skeletal maturity of children with multiple osteochondromas: is diminished stature due to a systemic influence?

BACKGROUND: Multiple ostechondromas (MO) is an autosomal dominant inherited disease caused by mutated exostosin genes. It mostly affects the long bones and can lead to growth disturbances, especially disproportionate short stature. Both the local effect on growth plates and the systemic influence of the gene disorder on growth mechanisms might explain the diminished stature. PURPOSE: The hypothesis of this study is that the diminished stature in adults with MO is due to a systemic influence, leading to early skeletal maturation and early closure of the growth plate. Therefore, in these patients the skeletal age in adolescence is hypothesized to be higher than the calendar age. METHODS: Radiographs of the left hand were collected from 50 MO-affected children. The skeletal age was calculated using these radiographs according to the Greulich-Pyle bone scale and was compared to the calendar age at the time of radiography. RESULTS: Children aged 3-12 years had a significantly lower skeletal age compared to their calendar age (p = 0.030). Children aged 12-17 years had a significantly higher skeletal age (p = 0.019), especially boys. Skeletal maturation in children with MO therefore differs from their peers. CONCLUSION: In this study, the skeletal age in younger children with MO is lower than their calendar age. For adolescents, particularly boys, this is reversed, suggesting an earlier or faster closure of the growth plates. These findings support a systemic influence of the gene defect on growth rate.

Intraosseous atypical chondroid tumor or chondrosarcoma grade 1 in patients with multiple osteochondromas.

BACKGROUND: The autosomal dominant condition multiple osteochondromas, formerly called multiple hereditary exostoses, is associated with a risk of malignant progression of osteochondroma into secondary peripheral chondrosarcoma. Most patients with multiple osteochondromas have exostosin-1 or exostosin-2 gene mutations. To our knowledge, it has not been previously reported that patients may also harbor intraosseous (central) chondroid neoplasms, enchondromas, or atypical chondroid tumors or central chondrosarcomas. The combination of osteochondroma and enchondromas also exists in patients with metachondromatosis, a disorder associated with a protein tyrosine phosphatase non-receptor type 11 gene mutation. This study aims to establish any correlation between multiple osteochondromas and intraosseous cartilaginous neoplasms. METHODS: We retrospectively reviewed all histologically proven intraosseous atypical chondroid tumors or chondrosarcomas in our prospective nationwide Dutch tertiary referral multiple osteochondromas database. Demographic, clinical, radiographic, histological, and genetic data were recorded. The institutional medical ethics review board approved the study. RESULTS: From 195 adult patients, seven (3.6%) were identified with intraosseous atypical chondroid tumor or chondrosarcoma World Health Organization grade 1 and had a mean age of forty-two years; five of these patients were male. In all cases, radiographic and genetic findings were consistent with multiple osteochondromas, not metachondromatosis; three patients had an exostosin-1 mutation, four patients had an exostosin-2 mutation, and no patients had a protein tyrosine phosphatase, non-receptor type 11 mutation. Six patients underwent successful operative treatment without complications or recurrences after a mean follow-up duration of forty-eight months (range, twelve to 144 months). One patient was scheduled for surgery after biopsy and histologic confirmation. Of the seven patients, five (71%) also developed a peripheral chondrosarcoma in a known osteochondroma during the study period. CONCLUSIONS: Apart from osteochondromas or peripheral chondrosarcomas, multiple osteochondromas are also associated with intraosseous chondroid neoplasms, potentially resulting in central chondrosarcoma. Therefore, intraosseous lesions should not automatically be regarded as innocuous in this patient population.