Purpose

To determine the clinical significance of fluid imbibition at the bone-cartilage interface seen on postoperative MRI scans after osteochondral grafting of chondral lesions of the knee.

Methods

Retrospective review of patients enrolled in a prospective cartilage repair registry. Included patients underwent osteochondral autografting or allografting of the knee, had minimum one year of clinical follow-up, and underwent at least two postoperative MRI scans. The primary outcome was reoperation for arthroscopic debridement and chondroplasty or graft revision. Secondary outcomes included the radiographic fate of fluid imbibition.

Results

A total of 48 knees in 46 patients were analyzed, with mean 39 months clinical follow-up. Nine patients (19%) had fluid imbibition on at least one postoperative MRI scan, all of whom received allograft. Of these, two (22%) required eventual graft revision, four (45%) underwent arthroscopic chondroplasty but did not require revision, and three (33%) did not require any additional surgery by final follow-up. No demographic or surgical variable was associated with the presence of fluid imbibition. Fluid imbibition was significantly associated with need for chondroplasty (p = 0.05), but not graft revision.

Conclusions

Fluid imbibition on postoperative MRI following osteochondral allografting of the knee is associated with the need for arthroscopic chondroplasty, but should not be interpreted as a sign of a failing graft.

Level of evidence

Level IV, Case Series.

Background

Fresh osteochondral allograft transplant (OCA) has good outcomes in the knee. However, donor tissue for patellar OCA is limited. Outcomes after nonorthotopic OCA of the patella using more readily available femoral condylar allograft (FCA) tissue have not been previously reported.

Purpose

To assess short-term magnetic resonance imaging (MRI) and minimum 2-year clinical outcomes of nonorthotopic patellar OCA using an FCA donor.

Study design

Case series; Level of evidence, 4.

Methods

A prospective institutional cartilage registry was reviewed to identify patients treated with patellar OCA using an FCA donor between August 2009 and June 2016. OCA plugs were obtained from the FCA at its trochlear-condylar junction and implanted into the recipient patellar lesion. Early postoperative MRI scans were graded by a blinded musculoskeletal radiologist using the Osteochondral Allograft MRI Scoring System (OCAMRISS). International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC), Knee Outcomes Survey-Activities of Daily Living (KOS-ADL), and pain visual analog scale (VAS) scores were collected preoperatively and at minimum 2 years postoperatively, and outcomes were compared using the paired t test.

Results

A total of 25 patients were included for clinical outcome analysis and 20 patients for MRI analysis. MRI scans obtained at a mean of 11.4 months (range, 6-22 months) postoperatively showed a mean total OCAMRISS score of 9.0 (range, 7-11); mean bone, cartilage, and ancillary subscores were 2.6, 3.7, and 2.6, respectively. At the latest follow-up (mean, 46.5 months; range, 24-85 months), postoperative improvements were noted in IKDC (from 45.0 to 66.2; P = .0002), KOS-ADL (from 64.3 to 80.4; P = .0012), and VAS (from 5.1 to 3.4; P = .001) scores, with IKDC and KOS-ADL scores above the corresponding previously reported minimal clinically important difference.

Conclusion

In this study, patellar OCA using nonorthotopic FCA led to significant short-term improvements in pain and patient-reported outcomes. The majority of nonorthotopic patellar grafts demonstrated full osseous incorporation and good restoration of the articular surface on MRI at short-term follow-up.

Background

Osteochondral allograft transplantation (OCA) is a recognized option for full-thickness articular cartilage defects of the knee, especially in the setting of large lesions or those involving the subchondral bone. Previous heterogenous studies of athletes have shown a 75% to 79% rate of return to play after the procedure.

Purpose

To define return-to-play rates in a cohort of elite collegiate and professional basketball players following osteochondral allograft of the knee.

Study design

Case series; Level of evidence, 4.

Methods

Prospectively collected data from an institutional cartilage repair registry were retrospectively reviewed. Patients were eligible for inclusion if they were collegiate or professional basketball players at the time of surgery. Patient demographics, lesion size and location, and surgical details were collected. Postoperative magnetic resonance imaging scans were scored with the OCAMRISS system. Time to return to play and pre- versus postoperative player performance were determined with publicly available internet resources.

Results

Eleven athletes (4 professional, 7 collegiate) with a total of 14 treated lesions (1 to the medial femoral condyle, 6 to the lateral femoral condyle, 5 to the trochlea, and 2 to the patella) were eligible for study inclusion. Mean lesion size was 509 mm². All patients underwent OCA through an arthrotomy, with fresh grafts. The overall rate of return to play at the same level of competition was 80%. Median time to return to play was 14 months (range, 6-26 months). Among players with available statistics, there was no significant reduction in any performance category.

Conclusion

OCA in elite basketball players results in an 80% return to previous level of competition, which is consistent with previous reports of athletes playing other sports. Osteochondral allografting is a reasonable option to consider for full-thickness cartilage lesions of the knee, even for elite jumping athletes.

Objective

To identify preoperative imaging-based indicators of knee degeneration that correlate with graft failure risk and postoperative clinical outcome scores after osteochondral graft treatment for chondral defects of the knee.

Design

Prospectively collected data from 113 patients (mean age, 34 years; 65% male) treated with mosaicplasty or osteochondral allograft transplantation (OCA) was reviewed. Four different aspects of knee degeneration were examined based on preoperative radiographs or magnetic resonance imaging: (1) Osteoarthritis using the Kellgren-Lawrence (KL) grading system, (2) meniscus volume, (3) meniscus quality, and (4) synovitis. Primary outcomes included graft failure, defined by removal/revision of the graft or conversion to arthroplasty, and patient responses to clinical outcome scores.

Results

Forty-one knees (36%) underwent mosaicplasty, and 72 knees (64%) underwent OCA. Mean duration of follow-up was 4.5 years (range, 2-14 years). A preoperative KL grade of ≥3 was correlated with increased failure rates (P = 0.01), lower postoperative International Knee Documentation Committee form (IKDC), Activities of Daily Living of the Knee Outcome Survey (KOS-ADL), and Overall Condition scores (P < 0.01), and decreased improvement in Overall Condition scores (P = 0.01). Within an individual tibiofemoral compartment, a preoperative meniscus volume grade of ≥3 (indicating <50% meniscus volume remaining) was correlated with increased condylar graft failure rates (P < 0.01). Preoperative meniscus quality and synovitis grades were not associated with graft failure rates or clinically meaningful differences in postoperative outcome scores.

Conclusions

Greater preoperative osteoarthritis and meniscus volume loss were correlated with increased graft failure rates after osteochondral graft treatment for chondral defects of the knee.

Objective

To identify preoperative imaging-based indicators of knee degeneration that correlate with graft failure risk and postoperative clinical outcome scores after osteochondral graft treatment for chondral defects of the knee.

Design

Prospectively collected data from 113 patients (mean age, 34 years; 65% male) treated with mosaicplasty or osteochondral allograft transplantation (OCA) was reviewed. Four different aspects of knee degeneration were examined based on preoperative radiographs or magnetic resonance imaging: (1) Osteoarthritis using the Kellgren-Lawrence (KL) grading system, (2) meniscus volume, (3) meniscus quality, and (4) synovitis. Primary outcomes included graft failure, defined by removal/revision of the graft or conversion to arthroplasty, and patient responses to clinical outcome scores.

Results

Forty-one knees (36%) underwent mosaicplasty, and 72 knees (64%) underwent OCA. Mean duration of follow-up was 4.5 years (range, 2-14 years). A preoperative KL grade of ≥3 was correlated with increased failure rates (P = 0.01), lower postoperative International Knee Documentation Committee form (IKDC), Activities of Daily Living of the Knee Outcome Survey (KOS-ADL), and Overall Condition scores (P < 0.01), and decreased improvement in Overall Condition scores (P = 0.01). Within an individual tibiofemoral compartment, a preoperative meniscus volume grade of ≥3 (indicating <50% meniscus volume remaining) was correlated with increased condylar graft failure rates (P < 0.01). Preoperative meniscus quality and synovitis grades were not associated with graft failure rates or clinically meaningful differences in postoperative outcome scores.

Conclusions

Greater preoperative osteoarthritis and meniscus volume loss were correlated with increased graft failure rates after osteochondral graft treatment for chondral defects of the knee.