Distinguishing between congenital phenomena and traumatic experiences: Osteochondrosis versus osteochondritis

Lumbosacral endplate contour defect is frequently observed concurrent with other lumbosacral abnormalities on spinal CT of French Bulldogs

Lumbosacral osteochondrosis has been previously described in large breed dogs with variable clinical signs. Its CT features are a contour defect at the dorsal aspect of either vertebral endplate, commonly with an adjacent fragment. Descriptions of this condition have not been previously published in an increasingly popular breed, French Bulldogs. Aims of this retrospective, descriptive, single center study were to evaluate CT lumbosacral abnormalities and the frequency of lumbosacral endplate contour defect in a large sample of French Bulldogs. The presence and location of lumbosacral endplate contour defect and the presence of a concurrent osseous fragment were recorded. Other abnormal CT findings such as L7-S1 disc herniation, cauda equina nerve roots compression or thickening, disc mineralization, endplate sclerosis, spondylosis deformans, S1 articular processes hypertrophy, transitional vertebrae, hemivertebrae, spina bifida, and block vertebrae were recorded. Lumbosacral CT abnormalities were present in 91.8% of dogs (168/183). The most common abnormality was an L7-S1 dorsal disc herniation (77.4%, 130/168). Among dogs with lumbosacral abnormalities, the frequency of a lumbosacral endplate contour defect was 47% (79/168). It mostly involved L7 (78.5%, 62/79) at its dorsolateral aspect (61.3%, 38/62). A mineralized fragment was identified in 62% of the defects (49/79). Endplate contour defects were most frequently seen with a concurrent disc herniation (93.7%, 74/79) causing nerve root compression in 63.3% (50/79) and with sclerosis (65.8%, 52/79). There was no definitive evidence of a relationship with clinical presentation in this sample of French Bulldogs; therefore, this finding should be interpreted with caution. The etiology remains unclear.

Autologous chondrocyte implantation in the knee is effective in skeletally immature patients: a systematic review

PURPOSE

This systematic review evaluated the efficacy and safety of autologous chondrocyte implantation (ACI) for chondral defects of the knee in skeletally immature patients. Current available data from patients reported outcome measures (PROMs) and complications were collected, analyzed, and discussed.

METHODS

This systematic review was conducted according to the PRISMA guidelines. The following databases were accessed in May 2022: PubMed, Google scholar, Embase, and Scopus. All the clinical studies investigating the efficacy of ACI to manage chondral defects of the knee in skeletally immature patients were accessed. Articles treating patients with surgical procedures other than ACI were not eligible, nor were studies with a follow-up shorter than 12 months.

RESULTS

Data from 9 studies (251 procedures) were collected. 32% (80 of 251) of patients were females. The mean length of follow-up was 44.2 ± 29.4 (range, 12-115) months. The mean age of the patients was 16.4 ± 0.7 (range, 15-17) years. The Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Document Committee (IKDC) increased of + 41.9/100 (P = 0.003) and + 33.2/100 (P =  < 0.0001) points, respectively. The Lysholm Knee Score improved of + 20.6/100 (P = 0.02) points. The Visual Analogue Scale (VAS) for pain reduced of - 3.6/10 (P = 0.004) points. The Tegner scale did not show any statistically significant improvement from baseline to follow-up (P = n.s.). The rate of graft hypertrophy was 12.5% (5 of 40 patients), and the rate of failure 5.6% (8 of 142 patients).

CONCLUSION

ACI for chondral defects of the knee is effective to improve PROMs in skeletally immature patients. The safety profile of ACI still remains controversial.

LEVEL OF EVIDENCE

III.

Osteophytes: The product of convergent evolution

The very reasonable suggestion, that diarthrodial joint and juxta-discal (vertebral centra-marginal) bony overgrowths (referred to as osteophytes) have different etiologies, has eluded previous confirmation. The prevailing perspective is that diarthrodial osteophytes represent the product of compressive forces and that those on the margins of vertebral centra result from traction and therefore are enthesial in derivation. If diarthrodial joint osteophytes result from intrinsic pressures, any surface responses would require transcortical nutritional support, easily recognized by en face microscopic examination. This contrasts with enthesially derived growth, the surface of which is characterized by Sharpey's fiber insertions. These are recognized as inverted cones with a central protrusion on examination of related bone surfaces. We hypothesize that diarthrodial and disc-adjacent osteophytes have a different pathophysiology, distinguishable on the basis of microscopic surface appearance. We pursued microscopic examination of the surfaces of osteophytes present on diarthrodial joints (hip, knee, elbow, costovertebral) and vertebrae (cervical, thoracic, and lumbar) from the CAL Milano Cemetery Skeletal Collection for presence of transcortical channels and the inverted cones of Sharpey's fiber insertions. Examination of 22 diarthrodial joint osteophytes reveals the presence solely of transcortical channels, while examination of 35 vertebral centra marginal osteophytes reveals the presence only of inverted cones. Findings are independent of age, gender, joint affected, position in the spinal column and osteophyte "severity." It is now evidenced that all osteophytes are not created equal. Diarthrodial joint osteophytes are endochondrally derived; vertebral centra osteophytes, enthesial in derivation. Different pathophysiology at least partially explain the clinical character of these processes.