Cell lines for the human intervertebral disc: nucleus pulposus and annulus fibrosis

Abstract

during the past months. Participants were excluded if they (i) exhibited concomitant pain from other knee structures; (ii) described current or previous physiotherapy for knee pain (prior 12 months); and (iii) knee or hip arthroplasty or osteotomy. Radiographic severity of TFJ OA was assessed from a semiflexed, posteroanterior weight-bearing short film radiograph with the feet externally rotated by 10 . Radiographic severity of PFJ OA was assessed from weight-bearing skyline radiographs, with the knee positioned at 30-40 knee flexion. Severity of radiographic OA was assessed by the same two examiners (KMC, RSH) from digital radiographic images, with meetings to discuss discrepant findings and obtain consensus when required. The Kellgren and Lawrence (K/L) score was assigned in a manner previously described in the literature, to both the TFJ and to the PFJ. Furthermore, separate gradings were conducted on the medial and lateral components of the PFJ. Inter-rater reliability (k) for grading TFJ and PFJ radiographic OA on a subset of 39 participants ranged from 0.745-0.843. Results: 224 individuals with chronic AKP (115 (51%) women, meanAESD: age 54AE10 yrs, height: 1.69AE0.10 m; weight 79AE15 kg; body mass index (BMI) 27AE4 kg.m -2 ) were recruited into this study. 67 (30%) had no radiographic OA, 57 (25%) had isolated PFJ OA, 2 (9%) had isolated TFJ OA and 98 (44%) had combined PFJ and TFJ OA. Within the TFJ, 123 (55%) had no TFJ OA, 56 (25%) had mild TFJOA and 45 (20%) had moderate/severe TFJ OA. For the lateral PFJ, 91 (41%) had no PFJ OA, 83 (37%) had mild PFJ OA and 50 (22%) had moderate/severe PFJ OA, while for the medial PFJ, 103 (46%) had no OA, 76 (34%) had mild PFJ OA and 45 (20%) had moderate/severe PFJ OA. In those 80 participants (36% of cohort) who were aged between 40 and 50 yrs (38 (48% women, age 45AE3 yrs; height 1.70AE0.10 m, weight 79AE17 kg, BMI 27AE5 kg.m -2 ), 36 (45%) had no radiographic OA, 21 (37%) had isolated PFJ OA, 1 (1%) had isolated TFJ OA and 22 (28%) had combined PFJ and TFJ OA. Conclusions: The majority (70%) of people presenting to this trial with chronic AKP had radiographic signs of OA. The prevalence of PFJ OA (67%) was greater than the prevalence of TFJ OA (51%), and the medial and lateral PFJ appeared to be affected similarly. The prevalence of radiographic OA was still considerable (55%) in individuals aged 40-50 years, with high rates of PFJ OA (54%). PFJ OA appears to be an important problem in individuals with chronic AKP and future studies need to investigate the link between AKP in individuals less than 40 years and the development of PFJ OA.

Importance of Matrix Cues on Intervertebral Disc Development, Degeneration, and Regeneration

“…Recent progress in identifying phenotypic markers for notochordal [68] and NP [29] cells has revealed that NP cells are derived directly from the notochordal cell population [69]. However, subpopulations of NP [70,71] and AF [72,73] cells with potentially differing ontogenies have been identified in adult IVDs, including those of non-notochordal origin. It is therefore speculated that a small notochordal cell population persists into adulthood, producing ECM that encourages the development of a healthy NP cell phenotype and guards against the onset of early IVD degeneration [74][75][76][77].…”