Osteochondral defects of the upper extremity treated with particulated juvenile cartilage transfer

Autologous Minced Cartilage Implantation for Arthroscopic One-Stage Treatment of Osteochondritis Dissecans of the Elbow

This Technical Note describes the full arthroscopic one-stage treatment of high-grade osteochondritis dissecans of the humeral capitellum of the elbow joint by means of minced cartilage implantation.

Both Debridement and Microfracture Produce Excellent Results for Osteochondritis Dissecans Lesions of the Capitellum: A Systematic Review

Purpose

To analyze the available literature pertaining to the indications, outcomes, and complications of both microfracture (MFX) and simple debridement for capitellar osteochondritis dissecans (OCD).

Methods

A comprehensive literature review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) criteria. Studies were included if they evaluated OCD of the capitellum that underwent either arthroscopic debridement (AD) or MFX. The risk of bias was assessed using the Methodological Index for Non-randomized Studies (MINORS) scale. Patient demographic characteristics, imaging findings, return-to-sport rates, patient-reported outcomes, range of motion (ROM), complications, failures, and reoperations were recorded.

Results

Eleven studies with 327 patients (332 elbows) met the inclusion criteria. Methodological Index for Non-randomized Studies (MINORS) scores ranged from 63% to 75% and showed considerable heterogeneity. Both AD and MFX showed improvement in patient outcome scores, ROM, and return to play, although the data precluded relative conclusions. Improvement in motion after MFX ranged from 4.9° to 5° of flexion, 5° to 22.6° of extension, 1° to 2° of pronation, and 0.5° to 2° of supination, whereas after AD, it ranged from –4° to 6° of flexion and –0.4° to 14° of extension, with prono-supination noted in only 1 study. The rate of return to play at a similar level of preinjury athletic competition ranged from 55% to 75% after MFX and from 40% to 100% after AD. Lesion location was discussed in only 1 study. Postoperative imaging trended toward early degenerative changes, most commonly of the radial head. Complications were only reported in 1 MFX study; in all cases, the complication was transient ulnar nerve neurapraxia. Reoperation rates ranged from 0% to 10%, and reoperation was most commonly performed to address radial head enlargement. Five studies reported no reoperations.

Conclusions

Both AD and MFX for capitellar OCD appear to yield excellent improvements in pain, ROM, patient outcome scores, and return to sport. Given that comparable mid-term outcomes can be achieved with debridement alone, without the use of MFX, similarly to recent prospective studies in the knee, AD alone may be a reasonable approach to relatively small OCD defects.

Level of Evidence

Level IV, systematic review of studies, all Level IV evidence.

The Use of Particulated Juvenile Allograft Cartilage for the Repair of Porcine Articular Cartilage Defects

BACKGROUND

The repair of porcine articular cartilage defects by using particulated juvenile allograft cartilage (PJAC) has demonstrated good short-term clinical efficacy, but the repair process and mechanism have not been fully elucidated.

PURPOSE

To study the efficacy of PJAC in repairing full-thickness cartilage defects and to provide an experimental basis for its clinical application.

STUDY DESIGN

Controlled laboratory study.

METHODS

Thirty Guizhou minipigs were randomly divided into an experimental group and control group. An 8-mm cylindrical full-thickness cartilage defect was created in the femoral trochlea of either knee in all minipigs. The experimental group received the PJAC transplantation (PJAC group; n = 15) and the control group received autologous cartilage chips (ACC group; n = 15). Five minipigs were euthanized at 1, 3, and 6 months in each group to obtain samples, which were evaluated by general view of the knee joint and histomorphometry of the chondral defect area (hematoxylin and eosin, safranin O). International Cartilage Repair Society (ICRS) II semiquantitative evaluation and collagen type II staining immunohistochemistry were also performed.

RESULTS

All 30 Guizhou minipigs were followed; there was no infection or incision healing disorder after the operation. At 1 month postoperatively, more hyaline cartilage was found in the ACC group (29.4%) compared with the PJAC group (20.1%) (P < .05); there was no statistical difference between the 2 groups at 3 and 6 months after operation. The fibrocartilage content in the ACC group was significantly more than that in the PJAC group at 1 and 3 months postoperatively (27.4% vs 18.2% and 49.9% vs 41.1%, respectively; P < .05); significant differences disappeared at 6 months postoperatively. The PJAC group produced more fibrous tissue than the ACC group at 1 and 3 months postoperatively (60.1% vs 40.6% and 38.8% vs 24.4%, respectively; P < .05) but showed no statistical difference at 6 months postoperatively. Regarding the ICRS II scores, those of the ACC group were significantly better than the scores of the PJAC group in some subclasses at 3 and 6 months postoperatively. The positive rates of immunohistochemical staining in the ACC group were higher at 1 and 3 months postoperatively than those in the PJAC group (54.2% vs 37.8% and 46.4% vs 34.4%, respectively; P < .05). The difference was not statistically significant between the 2 groups at 6 months postoperatively.

CONCLUSION

Both PJAC and ACC can produce a good repair effect on cartilage defects. At 1 and 3 months postoperatively, ACC resulted in better outcomes than PJAC, but there was no statistical difference in the repair effect between the 2 techniques at 6 months postoperatively.

CLINICAL RELEVANCE

Based on this animal experiment, further clinical studies are needed to investigate PJAC as a possible alternative first-line treatment for cartilage defects.

Patellofemoral Cartilage Lesions Treated With Particulated Juvenile Allograft Cartilage: A Prospective Study With Minimum 2-Year Clinical and Magnetic Resonance Imaging Outcomes

PURPOSE

To analyze the functional outcomes of patients treated with particulated juvenile articular cartilage (PJAC) for symptomatic articular cartilage lesions in the patellofemoral joint, correlates clinical outcomes with magnetic resonance imaging (MRI) appearance of the repair tissue using cartilage-sensitive quantitative T2-mapping.

METHODS

All patients treated with PJAC for patellofemoral lesions were identified and prospectively followed with clinical outcome scores (International Knee Documentation Committee [IKDC], Knee Outcome Survey-Activities of Daily Living [KOS-ADL], and Marx Activity Scale [MAS]). Postoperative MRI scans using quantitative T2 mapping were obtained and interpreted by an independent musculoskeletal radiologist.

RESULTS

Twenty-seven patients treated with PJAC for 30 full-thickness patellofemoral cartilage lesions were identified; mean postoperative follow-up was 3.84 years. Improvements from pre- to postoperative mean IKDC (45.9 vs 71.2, P < .001) and KOS-ADL (60.7 vs 78.8, P < .001) scores were observed; no significant change in MAS was seen (7.04 vs 7.17, P = .97). Advanced age, history of previous surgery, lesion location (patella vs trochlea), or concomitant tibial tubercle osteotomy did not affect outcome scores. Greater body mass index was associated with less improvement in KOS-ADL score. No patients required reoperation for graft-related issues. Lesion fill exceeding 67% by MRI assessment was noted in 69.2% of lesions; depth of lesion fill did not correlate with clinical outcomes. Quantitative T2-mapping revealed prolonged relaxation time at the graft site compared with adjacent normal cartilage at both deep and superficial zones.

CONCLUSIONS

This study found significantly improved pain and function in patients treated with PJAC for symptomatic patellofemoral articular cartilage defects. No patients required reoperation for graft-related issues. Postoperative MRI revealed majority lesion fill in more than 69% of patients, but persistent morphologic differences between graft site and normal adjacent cartilage remain. Though we support PJAC use in this setting to improve patient subjective outcomes, improved appearance on postoperative imaging was not found to provide additional clinical benefit.

LEVEL OF EVIDENCE

Level IV, case series.