The Effect of Surgical Insertion and Proinflammatory Cytokines on Osteochondral Allograft Survival and Metabolism

Objective To investigate the responses of refrigerated osteochondral allograft cartilage (OCA) and fresh cartilage (FC), including cell survival and metabolism, to surgical impaction and proinflammatory cytokines. Design Osteochondral plugs (8 mm diameter) were harvested from prolonged-refrigerated (14-28 days) and fresh (≤24 hours postmortem) human femoral hemicondyles and subjected to a 0.2 N s pneumatic impaction impulse. Cartilage explants were removed from subchondral bone and randomized to 1 of 6 treatment groups: (1) Unimpacted control (UIC), (2) Impacted control (IC), (3) Impacted + interleukin (IL)-1β (0.1 ng/mL), (4) Impacted + IL-1β (0.1 ng/mL) + IL-6, (5) Impacted + IL-1β (10 ng/mL), and (6) Impacted + IL-1β (10 ng/mL) + IL-6. Samples were measured for cell viability, histology, and proteoglycan (PG) content at days 0, 2, 7, and 14 of culture. Results In UIC, cell viability was indistinguishable between OCA and FC and remained constant. Impaction alone decreased cell viability by 30% ( P < 0.01) in the OCA superficial layer and by 26% ( P < 0.01) in the entire tissue, but did not affect viability in FC. Cytokine addition did not further influence cell viability. Impaction alone did not affect PG synthesis. Addition of cytokines to impacted tissue decreased PG synthesis by ~3-fold in both tissue types in comparison with corresponding impacted controls ( P < 0.01). Throughout 2-week culture, PG release remained stable in all FC groups, but peaked at day 14 in OCA cartilage subjected to cytokines. Conclusions Mechanical impaction, mimicking surgical insertion, has a more profound effect on cell viability in OCA than in FC. Addition of proinflammatory cytokines further decreases OCA tissue metabolism and integrity.

A novel terminal web-like structure in cortical lens fibers: architecture and functional assessment

This study describes a novel cytoskeletal array in fiber cells of the ocular lens of the rat and shows its relationship to the classical terminal web of other epithelial tissues. Naive adult Sprague-Dawley rats (n = 28) were utilized. F-actin, fodrin, myosin IIA, and CP49 distribution was assessed in anterior and posterior polar sections. For functional analysis, lenses were cultured with or without cytochalasin-D for 3 hr, then processed for confocal microscopy or assessed by laser scan analysis along sutures. Phalloidin labeling demonstrated a dense mesh of F-actin adjacent to posterior sutural domains to a subcapsular depth of 400 μm. Anterior polar sections revealed a comparable actin structure adjacent to anterior suture branches however, it was not developed in superficial fibers. Fodrin and myosin were localized within the web-like actin apparatus. The data was used to construct a model showing that the cytoskeletal array is located within the blunt, variable-width fiber ends that abut at sutures such that the "terminal web" flanks the suture on either side. Treatment with cytochalasin-D resulted in partial disassembly of the "terminal web" and perturbed cellular organization. Laser scan analysis revealed that cytochalasin-D treated lenses had significantly greater focal variability than control lenses (P = 0.020). We conclude that cortical fibers of rat lenses contain a bipolar structure that is structurally and compositionally analogous to classical terminal webs. The results indicate that the lens "terminal web" functions to stabilize lens fiber ends at sutures thus minimizing structural disorder, which in turn, promotes the establishment and maintenance of lens transparency.

Midterm results of surgical treatment for adult osteochondritis dissecans of the knee

BACKGROUND

Determination of appropriate treatment options for adult osteochondritis dissecans is difficult, as most published papers on surgical osteochondritis dissecans treatment report outcomes in a population consisting of both adult and juvenile patients.

PURPOSE

This study examines the outcomes of surgical procedures in patients with adult osteochondritis dissecans.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The cohort included 46 adult patients (48 knees) with adult osteochondritis dissecans of the knee who had undergone surgical treatment (debridement, drilling, loose-body removal, arthroscopic reduction and internal fixation, microfracture, osteochondral allograft, or autologous chondrocyte implantation). The average patient age was 34 +/- 9.5 years (range, 20-49) and patients were followed for 4.0 +/- 1.8 years. The mean defect size was 4.5 +/- 2.7 cm(2). Outcomes were assessed via clinical assessment and established outcome scales, including the Lysholm, International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Tegner, Cincinnati, and Short Form-12.

RESULTS

Statistically significant improvement (P < .05) was noted in all outcome scales, including Noyes, Tegner, Lysholm, IKDC, KOOS (subdivided into 5 categories including Pain, Symptoms, Activities of Daily Living, Sport, and Quality of Life), Short Form-12 Physical, and Short Form-12 Mental. Seven knees (14%) had clinical failure of the initial treatment and underwent a revision procedure at a mean follow-up of 14 months. Patients treated with arthroscopic reduction and internal fixation and loose-body removal demonstrated a statistically higher postoperative percentage score increase for the KOOS Sport (P = .008) and KOOS Quality of Life (P = .03) categories than those treated with an osteochondral allograft.

CONCLUSION

Patients with adult osteochondritis dissecans of the knee, treated with surgical cartilage procedures, show durable function and symptomatic improvement at a mean 4.0 years of follow-up. Patients treated with arthroscopic reduction and internal fixation and loose-body removal demonstrated a greater improvement in outcome scores than those treated with osteochondral allograft.

A randomized, prospective, double-blind study to investigate the effectiveness of adding DepoMedrol to a local anesthetic injection in postmeniscectomy patients with osteoarthritis of the knee

BACKGROUND

Patients with osteoarthritis of the knee are at risk for poorer outcomes after arthroscopic meniscectomy. Intra-articular corticosteroid injections have been shown to be efficacious both in patients with osteoarthritis and postarthroscopy patients.

HYPOTHESIS

A postoperative, intra-articular methylprednisolone and lidocaine injection in patients with chondromalacia undergoing meniscectomy will improve patient-rated pain and function compared with control patients.

STUDY DESIGN

Randomized, controlled trial; Level of evidence, 1.

METHODS

A total of 58 patients (59 knees) were randomized in a double-blinded fashion to receive either saline plus lidocaine (saline) or methylprednisolone plus lidocaine (steroid) after arthroscopic meniscectomy in which chondromalacia (modified Outerbridge grade 2 or higher) was confirmed. Preoperatively and at follow-up-6 weeks and 6, 9, and 12 months-patients underwent an examination and completed a subjective functioning survey. Scores were calculated using several validated scoring systems including the Lysholm, International Knee Documentation Committee (IKDC), and Short Form-12 (SF-12).

RESULTS

No statistically significant differences were observed between the saline (n = 30) and steroid (n = 29) groups in their demographics and preoperative scores. At 6 weeks, the steroid group had higher scores than the saline group on multiple scales, including the IKDC. No differences in outcome scores existed at later time points. At 12 months, 86% of the steroid and 69% of the saline group were completely or mostly satisfied with the procedure (P = .01). In the saline group, 4 patients required reinjection and 2 underwent joint replacements within 12 months, while the steroid group had 3 reinjections and 2 meniscus transplants.

CONCLUSION

The addition of a postoperative corticosteroid injection resulted in improved pain and function at an early time point; however, it provided no lasting difference compared with only local anesthetic injection.