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The architecture of the diaphyseal bone is closely correlated with the cortical vessel network, whose pattern develops in the course of growth. Various methods have been applied to clarify the three-dimensional anatomy of the cortical canal system, but there is still disagreement about the geometry, blood supply, flux dynamics and factors controlling canal geometry during bone growth and remodeling. A modification of the currently employed dye-injection method was applied to study the vessel network of the whole hemi-shaft of the rabbit femur in mature bones (8-month-old rabbits) and growing bones (1.5-month-old rabbits). The cortical vascular tree of the hemi-shaft of the femur was injected with black China ink and observed in full-thickness specimens of the cortex. The same specimens were then processed for histology. A comparative study of the middle diaphysis (mid-shaft) with the distal extremity (distal shaft) was performed in both young and old rabbit femurs. The longitudinally oriented pattern of the vessel network was seen to develop in the diaphysis of mature femurs, while at the extremity of the shaft of the same specimen the network showed a reticular organization without a dominant polarization. The vessels were significantly higher in the mid-shaft than in the distal shaft of the old femurs ( P < 0.0001), as was their diameter ( P < 0.05). In the group of young rabbits at mid-shaft level the longitudinally oriented pattern of the vessel network was not yet completely developed, without their being significant differences in length and diameter between the mid-shaft and distal shaft. The differentiation of the mid-shaft from the distal shaft was confirmed histologically by the presence, in the latter, of longitudinal calcified cartilage septa between osteons. This pattern of structural organization and development of the intracortical vascular network has not been previously reported. The cells primarily involved in polarization of the remodeling process were the osteoclasts at the top of the cutting cones advancing from the proximal and distal metaphyses toward the midshaft. This suggests, first, a relationship with the longitudinally oriented structures already present in the cortex near the metaphysis (the calcified cartilage septa) and then with the columns of interosteonic breccia, which were formed as a secondary effect of the longitudinal polarization of the remodeling process. Our observations did not enable us to substantiate the model of two different systems, one of longitudinal vessels (Havers) and the other of connecting transversal vessels (Volkmann), but suggested instead that there is a network whose loops lengthen in the direction of the major bone axis in the course of growth and secondary modeling. The associated morphology supported the view that the type of structural organization of the tubular bone cortex is primarily determined by an inherited constitutional factor rather than by mechanical strains.

Background. Shoulder overuse, both occupational and sports-related, is a major cause of shoulder pain with an estimated incidence of 0.9%-2.5% in the general population and a prevalence of 7%-27% in Europe and United States. We report on a young amateur bodybuilder presenting with a complex shoulder overuse lesion. A posterior labrum periosteal sleeve avulsion (POLPSA) with a chondral lesion of the posterior glenoid cavity and a SLAP lesion was diagnosed. Case presentation. A 33-year-old male construction worker complained of 9 months worsening right shoulder pain. He was an amateur body builder who would bench press heavy weights (up to 170 kg). A magnetic resonance arthrogram showed a posterior labrum sleeve avulsion, a stress chondral fracture of the posterior glenoid cavity and a SLAP lesion. Arthroscopic repair of the bicipital anchor, posterior labrum fixation and removal of the chondral fragment, proved successful and allowed the patient to return to his previous sports activity. Conclusions. Bench press creates major forces along the anteroposter axis of the upper limbs, pushing the humeral head posteriorly and increasing joint reaction force on the posterior glenoid quadrant considerably as the scapula is locked resting on the bench. This may result in a tendency for the humeral head to subluxate posteriorly which, aggravated by the high number of repetitions, puts the posterior labrum and capsula under very high stress eventually leading to labrum failure. Arthroscopic repair was shown to restore shoulder function in these athletes.

Objective Knee osteochondritis dissecans (OCD) is a still poorly understood pathological condition of the articular subchondral bone and its overlying cartilage. Patellofemoral involvement accounts for less than 1% of cases; tibial plateau and multifocal involvement is an even rarer instance. The purpose of this study is to review what is currently known about patellofemoral OCD (PF-OCD) and to present an unusual case of PF-OCD which progressed to become multifocal in an adult female patient. Methods A comprehensive literature search was conducted on PubMed/Medline, Cochrane, Embase, Web of Science, and Scopus databases on September 2021 for all levels of evidence and English language. After duplicate removal, 234 papers pertaining to PF-OCD were retrieved. Thirty-nine studies met inclusion criteria and were included in the review. As an example, a unique case of delamination of patellar cartilage consistent with PF-OCD with progressive involvement of trochlea and both tibial plateau in a 35-year-old woman is also presented. Results PF-OCD is a rare localization of knee OCD. Two hundred eighty-eight cases have been reported in the literature to date. Mean age at time of diagnosis was 16 years and the location could also be bilateral and multifocal. The etiology is still debated but traumatic, vascular, and hereditary mechanisms are likely. Management mirrors that of classical OCD. Conclusions PF-OCD is an uncommon cause of anterior knee pain but should be considered even when physeal plates are closed. Current available evidence on treatment is of low quality, based on single case reports or small retrospective case series.

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