ABSTRACT:
OBJECTIVE Focal osteochondral lesions of the knee are found in two thirds of patients
undergoing arthroscopy; their treatment, when isolated and especially in
young individuals, remains a debating topic. The present study analyzes the
results obtained by the application of the mosaicplasty technique on the
treatment of isolated knee femoral condyle osteochondral lesions.
METHODS Retrospective study of patients submitted to mosaicplasty and to subjective
analyses with pre- and postsurgery International Knee Documentation
Committee (IKDC) scores.
RESULTS A total of 13 cases with an average age of 34 years old, with male patients
(n = 4; 31%) with an average age of 23 years old
(range: 17–31 years old), and female patients (n = 9; 69%)
with an average age of 39 years old (range: 16–56 years old); medial versus
lateral femoral (n = 11; 85% versus n = 2;
15%); the average size of the lesion was 1.8 cm2 (range: 0.6–4
cm2); average follow-up time: 5.045 ± 3.47 years
(range: 1.15–11.01 years). The average preoperative IKDC score was of 31.63
points (±20.24), the average postoperative IKDC score was of 74.18
points (±20.26). The difference between the post- and preoperative
IKDC scores was of 42.55 (±21.05) points, being the minimal score
increase of 8.1 points and the maximum score increase of 82.8 points. A
statistically significant difference (p < 0.001) was
found between the IKDC scores before and after the surgery. A statistically
significant relation (p = 0.038) was found between the IKDC
score increase (the difference between the postoperative and the
preoperative scores) and the dimension of the lesion.
CONCLUSIONS Mosaicplasty with osteochondral autograft transfer, when adequately used, can
produce excellent results with great durability and functional impact, low
morbidity rates and costs. Expansion of the indication criteria shows
promising mid-term and long-term results.
Keywords: osteochondritis/diagnosis; osteochondritis/surgery; arthroscopy; knee joint; cartilage, articular.
RESUMO:
OBJETIVO Lesões osteocondrais focais do joelho são encontradas em dois terços dos
pacientes submetidos a artroscopia; seu tratamento, quando isoladas e,
principalmente, em indivíduos jovens, ainda é debatido. O presente estudo
analisa os resultados obtidos com a aplicação da técnica de mosaicoplastia
no tratamento de lesões osteocondrais isoladas do côndilo femoral do
joelho.
MÉTODOS Estudo retrospectivo de pacientes submetidos à mosaicoplastia e análise
subjetiva com pontuações do International Knee Documentation Committee
(IKDC, na sigla em inglês) antes e após a cirurgia.
RESULTADOS Um total de 13 casos, com média de idade de 34 anos; pacientes do sexo
masculino (n = 4; 31%) apresentaram média de idade de 23
anos (17–31 anos), e pacientes do sexo feminino (n = 9;
69%) apresentaram média de 39 anos; (16–56 anos); femoral medial ou lateral
(n = 11, 85% versus
n = 2, 15%, respectivamente); o tamanho médio da lesão foi
de 1,8 cm2 (0,6–4 cm); o tempo médio de acompanhamento foi de
5,045 ± 3,47 anos (1,15–11,01 anos). A pontuação IKDC média
pré-operatória foi 31,63 pontos ( ± 20,24), e a pós-operatória foi
74,18 pontos ( ± 20,26). A diferença entre as pontuações IKDC obtidas
depois e antes da cirurgia foi de 42,55 ( ± 21,05) pontos, com o
aumento mínimo de 8,1 pontos e o aumento máximo de 82,8 pontos. Uma
diferença estatística significativa (p < 0,001) foi
encontrada entre a pontuação IKDC antes e após a cirurgia. Uma relação
estatisticamente significativa (p = 0,038) foi observada
entre o aumento da pontuação IKDC (a diferença entre a pontuação pré- e
pós-operatória) e as dimensões da lesão.
CONCLUSÕES A mosaicoplastia com transferência de autoenxerto osteocondral, quando
adequadamente usada, pode produzir resultados excelentes com grande
durabilidade e impacto funcional, baixas taxas de morbidade e baixos custos.
A expansão dos critérios de indicação mostra resultados promissores no médio
e longo prazo.
Palavras-chave: osteocondrite/diagnóstico; osteocondrite/cirurgia; artroscopia; articulação do joelho; cartilagem articular.
FIGURES
| Citation: Karmali S, Guerreiro R, Costa DS, Fonseca J, Gonçalves R. Mosaicplasty Technique in the Treatment of Isolated Knee Femoral Condyle Osteochondral Lesions – a Retrospective Study*. 54(3):316. doi:10.1055/s-0039-1691763 |
| Note: * The present study was conducted at the Orthopedic Department, Hospital Vila Franca de Xira, Portugal. |
| Received: January 07 2018; Accepted: May 28 2018 |
INTRODUCTION
Focal osteochondral lesions of the knee are found in two thirds of patients undergoing arthroscopy.1 The treatment of these lesions, when these are isolated and especially in young individuals, remains a debating topic.2-4 Knee replacement surgery is not a good solution, and a technique that can restitute ad integrum, a normal hyaline cartilage articular surface, still does not exist.2,4-6 Presently, the available techniques follow principles of palliation (debridement and chondroplasty), repair (microfracture), and autologous chondrocyte implantation (ACI) restoration, osteochondral autograft transfer (OTA), and osteochondral allograft (OCA).2,3 The former, in which we can include mosaicplasty (OTA), has been applied mainly for symptomatic relief and in an attempt to regain an articular surface with biofunctional properties similar to those of an injured joint, aiming for function preservation and less progression of the osteoarticular disease.2,7-9 The present study aims to analyze the results obtained by the application of the mosaicplasty technique on the treatment of isolated knee femoral condyle osteochondral lesions.
METHODOLOGY
Retrospective analyses of patients with knee osteochondral lesions, selected and submitted to the mosaicplasty repair technique in our institution between 2001 and 2015. The inclusion criteria were: patients ≤ 60 years old, with single osteochondral femoral condyle lesion (Outerbrige III/IV) < 4 cm2 in the preoperative MRI (International Cartilage Repair Society – ICRS) and confirmed arthroscopically, with follow-up of at least 1 year. Patients with associated lesions (e.g., tibia or patella), malalignment, or previous realignment surgery, were excluded (► Table 1).
| Inclusion criteria |
| Age ≥ 16 years old and ≤ 60 years old |
| Isolated femoral condyle osteochondral lesion |
| Grade III/IV (Outerbrigde) |
| Size ≤ 4 cm2 |
| Follow-up > 1 year |
| Exclusion criteria |
| Associated lesions (e.g., tibia or patella) |
| Malalignment or previous realignment surgery |
| Ligamentar instability |
| Inflammatory disease |
The procedure was performed using the Osteochondral Autograft Transfer System (OATS) (Arthrex, Inc., Naples, FL, USA) and according to the technique described by Hangody7, by arthroscopy with a mini arthrotomy for graft harvesting and transfer from its location (trochlear circumferential non-weight bearing area) to the osteochondral defect. (► Fig. 1). Postoperative protocol with weight bearing restriction for 2 weeks, followed by partial weight bearing (10–20% of the body weight) until the 6th week, total weight bearing until 6 months, and unrestricted activity thereafter.

The patients were submitted to subjective evaluation with the International Knee Documentation Committee (IKDC) form, in the period between the lesion and the surgery, and again 1 year after the surgery. Data analyses were made with IBM SPSS Statistics for Windows, Version 22.0 (IBM Corp., Armonk, NY, USA).
RESULTS
From the analyses of the 13 cases eligible for the present study (► Table 2), we have found an average age of 34 years old, with male patients (n = 4; 31%) with an average age of 23 years old (range: 17–31 years old), and female patients (n = 9; 69%) with an average age of 39 years old (range: 16–56 years old). Lesions affected more the medial femoral condyle compared with the lateral (n = 11; 85% versus n = 2; 15%) and the observed average size of the lesion was 1.8 cm2 (0.6–4), 7 of which were > 2 cm2. The average follow-up time of the patients was of 5.045 ± 3.47 years (range: 1.15–11.01 years). During the 1st year, none of the patients developed infections or complications in the donor site; 1 of the patients (female, 54 years old) was submitted to a total knee arthroplasty (TKA) 13 months after the mosaicplasty (6 years later, the TKA was revised). The average preoperative IKDC score was of 31.63 points (±20.24), whereas the average postoperative IKDC score was of 74.18 points (±20.26). The difference between the post- and preoperative IKDC scores was of 42.55 (±21.05) points, being the minimal score increase of 8.1 points, and the maximum score increase of 82.8 points (► Fig. 2). A statistically significant difference (p < 0.001) was found between the IKDC scores before and after the surgery – paired samples Wilcoxon test (► Fig. 3). Statistically significant correlations between the IKDC score and age or gender were not found. However, a statistically significant relation (p = 0.038) was found between the IKDC score increase (the difference between the postoperative and the preoperative scores) and the dimension of the lesion.
| n | Age (years) | Gender* | Localization** | Size (cm2) | Preoperative IKDC | Postoperative IKDC | Follow-up (years) |
|---|---|---|---|---|---|---|---|
| 1 | 25 | M | MFC | 1 | 79.3 | 100 | 3.00 |
| 2 | 16 | F | MFC | 3 | 46 | 90.8 | 11.01 |
| 3 | 16 | F | LFC | 4 | 36.8 | 88.5 | 11.01 |
| 4 | 17 | M | MFC | 2 | 3.3 | 44.8 | 8.01 |
| 5 | 54 | F | MFC | 1 | 54 | 62.1 | 6.79 |
| 6 | 18 | M | MFC | 3 | 18.4 | 92 | 4.00 |
| 7 | 36 | F | MFC | 2 | 17.2 | 100 | 2.00 |
| 8 | 30 | F | LFC | 1 | 40.2 | 85.1 | 3.00 |
| 9 | 42 | F | MFC | 0.6 | 17.2 | 44.8 | 2.36 |
| 10 | 48 | F | MFC | 2 | 12.6 | 72.4 | 1.15 |
| 11 | 56 | F | MFC | 0.9 | 27.6 | 50.6 | 2.78 |
| 12 | 31 | M | MFC | 1 | 34.5 | 74.7 | 7.97 |
| 13 | 53 | F | MFC | 2 | 24.1 | 58.6 | 2.51 |


DISCUSSION
The treatment of articular cartilage lesions comprises procedures of palliation (debridement and chondroplasty), repair (microfracture), and reconstruction (ACI, OTA, and OCA).2,4,10 Their application is driven by clinical and morphological criteria. According to the most recent literature reviews that discuss the treatment of osteochondral lesions of the knee, lesions with dimensions < 2 cm2 are best treated through microfracture (first-line option) or OTA.11 The latter shows more longevity and durability of results, especially among high functional demand patients, when compared with microfractures.3,4 When lesions range from 2 to 4 cm2, they should be treated by OTA or by ACI.3 Regarding lesions with dimensions ≥ 4cm2, OTA morbidity is not neglectable, which is a reason why these should be approached with ACI or OCA (being the latter especially applied in extensive post-traumatic lesions or osteochondritis dissecans).3 Osteochondral autograft transfer, like other reconstructive techniques, confers good symptomatic and functional results and prevents the progression of degenerative changes. Moreover, it presents some advantages, such as its low cost, the absence of immunological reactions and of infectious transmission (when compared with OCA), and can be performed in a single surgical time.2,3,7-9 This procedure, when used in lesions ranging from 2 to 4 cm2, has more efficacy and durability; as shown in our study (which analyzed lesions up to these dimensions), a correlation with statistical significance between the gain in IKDC scores and the lesion size can be made. The known complication rate is low, as observed in our study group. Results tend to be good in the medium to long term, being worse with increasing age, in females, and in greater size defects (> 4 cm2).2,3 The significant improvement in the IKDC score seen in our study, when comparing the pre- and postoperative status, is in line with other recent studies that use this or other functional evaluation scores.9,12,13
CONCLUSION
Hyaline cartilage regeneration is not possible nowadays, and remains the greatest goal to be achieved in the treatment of osteochondral lesions. Mosaicplasty with OTA, when adequately used, can produce excellent results, with great durability and functional impact, low morbidity rates and costs. Although it has restricted indications, expansion of the criteria for its use has shown promising mid-term and long-term results, as shown in the recent literature.




