Osteochondritis dissecans (OCD) is an incompletely understood joint disorder affecting a broad spectrum of patients, but is most prevalent in adolescents and young adults. It is the end result of the aseptic separation of an osteochondral fragment with the gradual fragmentation of the articular surface and results in an osteochondral defect. The incidence of OCD is estimated to be approximately 15 to 30 per 100,000 patient-years. OCD lesions are most frequently seen in the knee. Reconstructive techniques for OCD of the knee are typically necessary when either non-operative or reparative/regenerative operative treatments fail, or when the OCD is irreversible. Although a limited number of low-level evidence studies concening the use of fresh osteochondral allograft in the treatment of the OCD as reconstructive technique are available in previous research, satisfactory clinical results and survival rates of the reconstruction are reported.
Osteochondritis dissecans (OCD) is an incompletely understood joint disorder affecting a broad spectrum of patients, but is most prevalent in adolescents and young adults [1]. The incidence of OCD is estimated to be approximately 15 to 30 per 100,000 patient-years [2][3]. OCD lesions are most frequently seen in the knee, occurring most often in the medial femoral condyle (70%, especially in the lateral aspect of the medial femoral condyle), followed by the lateral femoral condyle (15–20%), patella (5–10%), and trochlea (<1%) [4][5]. Although OCD was first described over 100 years ago, there is no consensus on its etiology. The original nomenclature suggested a major role for inflammation in OCD; however, histological evidence has failed to support this theory [6]. Current hypotheses on the origin of OCD include repetitive microtrauma, vascular insufficiency, or anomalous endochondral ossification [7]. This pathologic process involves the fragmentation of subchondral bone, which becomes avascular and detaches from the surrounding cartilage, often forming an intra-articular loose body [8]. The lesion can manifest as pain or through other symptoms, including catching and locking [2]. Age and skeletal maturity are important variables influencing clinical decision making because older, skeletally mature individuals (in the setting of lower healing potential) are less likely to succeed with non-operative treatment and more likely to progress to surgery [9][10].
The non-operative treatment of OCD with activity modification and bracing has been reported to be successful in 50% to 94% of patients with open physes and stable lesions [11][12]; therefore, most authors suggest initial non-operative treatment for juvenile OCD [9][13][14][15][16][17][18][19]. In the cases in which the physes are closed or the lesion is advanced—particularly in stage 3 (unstable but not dislocated fragment) or stage 4 (presence of loose body) according to the classification system proposed by Clanton and DeLee [20]—the success of non-operative treatment decreases [21]. Both reparative techniques, such as internal fixation [16][17][22], bone grafting [23], or debridement/fragment excision [24][25], and restoration techniques, such as anterograde/retrograde drilling [16][26][27] and autologous chondrocyte implantation (ACI) [28], have demonstrated variable healing outcomes. Large OCD de novo lesions, or those that progress after unsuccessful initial treatment and present with significant bone and cartilage defects, lead to long-term disability and are precursors to osteoarthritis at a young age [13][14]. These defects in children or adults should be considered for reconstructive treatment options, including various techniques using the bone of synthetic grafts associated with ACI [29][30], autologous osteochondral transplantation (OAT) or mosaicplasty (when multiple plugs are harvested to fill the defect in a mosaic-like pattern) [31][32][33][34] and osteochondral allograft (OCA).
Hypothetically, OCA is an attractive option because it can restore in a single-stage procedure both the bone and chondral components, potentially with neither the pitfalls of mosaicplasty (principally the morbidity of the donor zone of the knee, which limits the dimensions of the reconstruction), nor the high costs of the ACI-related procedures. The major indications for OCA transplantation include substantive joint surface compromise (>2 cm 2) with bone loss and/or failed prior cartilage repair. Pathologic OCD tissue can be removed by cylindrical drills and replaced by press-fit “dowel grafts” (if necessary, fixation can be augmented with bioabsorbable screws or chondral darts) or resected to create a flat surface for the application of “shell grafts” [35]. The latter usually requires fixation to maintain compression (typically achieved by bioabsorbable or cannulated screws), although mixed methods have been described [36]. OCA can be fresh, frozen, cryo-preserved or freeze-dried tissue bank products. Stored allografts have shown reduced antigenicity and risk of disease transmission, but the preservation process also affects the biomechanical competency of the transplant [37][38]. Since it is relatively accepted that cartilage viability positively correlates with the integration of the graft, and consequently with the clinical outcome, fresh osteochondral allografts (FOCA) are preferred. FOCA transplantation procedures offer the primary advantage of containing viable hyaline cartilage and structurally competent bone. The term “fresh” refers to a graft harvested within 24 h of the donors’ death, stored (usually at 4 °C into an appropriate culture) until microbiological and viral tests are performed and then transplanted into a recipient host, usually within 28 days to avoid viability decrease [39].
An in-depth search of the scientific research was performed according to PRISMA. A search regarding the existing evidence for clinical healing out-comes and failure rates of FOCA transplantation of the knee joint in OCD population with no restriction on date of publication, up to the end of September 2021, was performed on the PubMed, Scopus, and Web of Science databases. The inclusion criteria were as follows: original research reporting clinical outcomes and failure rates of FOCA for the treatment of osteochondritis dissecans in the knee joint, English language, minimum of five patients, minimum follow-up of 12 months, and human studies. Only studies reporting data on homogeneous populations of patients with OCD, or from which data regarding patients with OCD were extractable, were included.
Year | Authors [Reference] |
Patient, n° (OCA, n°) | Study Design (Level of Evidence) | Knee Site (%) | Age, y: Mean ± SD (Range) | FU, y: Mean ± SD (Range) | Lesion Size, cm2: Mean ± SD (Range) | Failure at Last FU, n° (%) | Estimated Graft Survival Rate | Re-Operation Rate * | Mean Time to Failure, y Mean ± SD |
---|---|---|---|---|---|---|---|---|---|---|---|
2018 |
Cotter et al. [43] |
37 (43) | Case series (IV) | LFC 44% MFC 51% Both condyles 4% |
26 ± 9.96 (15–49) |
7.29 ± 3.3 | 4.6 ± 1.7 | 2 (5.1%) | 97% at 5 years | 35.9% | 6.2 ± 3.8 |
2016 |
Sadr et al. [2] |
135 (149) | Case series (IV) | MFC 62% LFC 29% Trochlea 6% Patella 1% Others 2% |
Median. 21 (12–55) | Median: 6.3 (1.9–16.8) | 7.3 (2.2–25) | 12 (8%): 7 OCA revision, 3 UKA, 2 TKA | 95% at 5 years 93% at 10 years |
23% | 6.1 ± 4.5 |
2012 |
Lyon et al. [40] |
11 (12) | Case series (IV) | MFC 31% LFC 54% Patella 7.5% Trochlea 7.5% |
15.2 (13–20.4) | 2 (1–3.4) | 5.1 (1.8–8) | 0% | 100% at last FU | 0% | NA |
2009 |
Pasqual-Garrido et al. [42] |
46 (16) | Case series (IV) | NA | 34 ± 9.5 (20–49) ** |
4.0 ± 1.8 (2.0–10.6) ** | 4.5 ± 2.7 (0.9–15) ** | 1/16 OCA (6%): TKA | 94% at last FU ** | NA | 14 months |
2007 |
Emmerson et al. [41] |
64 (66) | Case series (IV) | MFC 62% LFC 38% |
28.6 (15–54) | 7.7 (2–22) | 7.5 | 9 (13%): 6 OCA revision, 1 OCA removal, 1TKA, 1 UKA | 91% at 5 years 76% at 10 and 15 years |
10 (15%) | 4.9 ± 2.4 |
1994 |
Garrett et al. [44] |
17 (17) | Case series (IV) | LFC 100% | 20 (16–46) | 3.5 (2–9) | NA | 1 (6%): not specified reconstructive surgery | 94% at last FU | 17 (100%): 1 failure + 16 hardware removal | 15 months |
Cotter et al., 2018 | Sadr et al., 2016 | Lyon et al., 2012 | Pasqual-Garrido et al., 2009 | Emmerson et al., 2007 | ||
---|---|---|---|---|---|---|
18-point | NA | Pr: 13.6 (±2.0) F: 16.8 (±1.5) p: <0.001 * |
Pr: 12.7 (10–14) F: 16.3 (10–18) |
NA | Pr: 13.0 ± 1.7 F: 16.4 ± 2.0 p: <0.01 * |
|
IKDC total score | Pr: 31 F: 59 p: <0.001 * |
Pr: 44.2 (± =17.5) F: 82.3 (± =15.8) p: <0.001 * |
NA | Pr: 31 F: 45 p: 0.15 |
NA | |
KOOS | Symptoms | Pr: ≈52 F: ≈69 p: <0.001 * |
NA | NA | Pr: 52 F: 74 p: 0.002 * |
NA |
Pain | Pr: ≈50 F: ≈70 p: <0.001 * |
Pr: 59 F: 67 p: 0.270 |
||||
ADL | Pr: ≈61 F: ≈82 p: <0.001 * |
Pr: 57 F: 67 p: 0.200 |
||||
Sport | Pr: ≈23 F: ≈51 p: <0.001 * |
Pr: 32 F: 46 p: 0.037 * |
||||
QOL | Pr: ≈21 F: ≈51 p: <0.001 * |
Pr: 29 F: 39 p: 0.062 |
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SF-12 | Physical | Pr: ≈33 F: ≈41 p: <0.001 |
NA | NA | Pr: 42 F: 52 p: 0.112 |
NA |
Mental | Pr: ≈53 F: ≈53 p: 0.910 |
Pr: 40 F: 43 p: 0.370 |
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VAS | NA | NA | Pr: 5.6 F: 1.2 |
NA | Pr: 6.7 ± 2 F: 0.9 ± 1.3 |
|
Satisfaction at Final FU, % (details) |
81% (Es: 50%; S: 31.6%) |
95% (Es: 78%; S: 17%; Ss: 3%; Sd: 1%; D: 1%) |
NA | 63% | 92% |
Abbreviations: Pr, preop. value; F, final FU value; p, p-value; 18 point, modified Merle d’Aubigné-Postel scale; IKDC, International Knee Documentation Committee; KOOS, knee injury and osteoarthritis outcome score; QOL, quality of life; ADL, activities of daily living; SF-12, 12 Item Short Form Survey; VAS, visual activity score; Es, extremely satisfied; S, satisfied; Ss, somewhat satisfied; Sd, somewhat dissatisfied; D, dissatisfied; NA, not available. * Statistically significant.
This entry is adapted from the peer-reviewed paper 10.3390/life11111205