Outcomes Of Osteochondral Allograft Transplantation Research Articles

Outcomes of Osteochondral Allograft Transplantation: A Comparative Study of BioUni and Snowman Techniques for Ovoid Lesions.

Treatment of large articular cartilage lesions of the knee includes surgical options one of which includes cartilage replacement therapies. Among these therapies include osteochondral allograft (OCA) transplantation, which can be performed utilizing a BioUni® (Arthrex BioUni® Instrumentation System; Arthrex, Naples, FL) replacement and a 'snowman' technique of repair. To compare clinical and radiographic outcomes in patients who have undergone multiplug OCA transplantations utilizing a BioUni® replacement and a 'snowman' technique of repair. Patients who underwent OCA transplantation utilizing a snowman technique or BioUni® replacement between January 1st, 2012 and December 31st, 2018, and who had a minimum 1-year follow-up at the same institution were identified for inclusion in this study via current procedural terminology (CPT) codes. Charts of included patients were reviewed for injury and treatment details as well as demographic information. Imaging studies and operative reports were reviewed and pre and postoperative subjective and objective outcome measures were recorded. Twenty-eight patients underwent OCA transplantation with either BioUni® replacement (n=5) or with snowman technique repair (n=23). Defects in both groups had similar characteristics including size, area, location, and classifications. Patient-reported outcomes using the Knee Injury and Osteoarthritis Outcome Score-Joint Replacement (KOOS-JR), International Knee Documentation Committee (IKDC), and Physical Health Composite Score (PCS-12) were similar at baseline and increased post-operatively for both groups with no significant differences between techniques after a mean follow-up of 2.77 ± 0.83. Although it did not reach significance, the snowman group had higher rates of knee-related complications (13%) and need for revision surgery (22%) when compared to BioUni® (0% and 0%, respectively). The use of both BioUni® and snowman techniques for large, unicondylar articular cartilage lesions of the femoral condyle demonstrate improved patient-reported outcomes at short-term follow-up. The use of the snowman technique presents relatively higher rates of revision similar to previous studies with no statistical difference in patient-reported outcomes when compared to those of a single plug OCA using a BioUni® system.

Osteochondral allograft transplantation in the football player (knee and ankle)

Articular cartilage defects in the knee and ankle are frequently seen in football (soccer) players and are often a result of trauma, but occasionally are the consequence of occult underlying conditions such as osteochondritis dissecans. Symptoms such as pain, swelling, and inability to ramp up may limit an athlete's performance and ability to compete. Initial evaluation includes a careful history and physical exam, including assessment of overall limb and joint alignment, ligamentous stability, meniscal damage, as well as associated degenerative change. Though nonoperative management serves as the mainstay for treatment in high-level athletes, surgical options are indicated in situations where symptoms persist. Osteochondral allograft (OCA) transplantation, in particular, allows for restoration of hyaline cartilage with predictable healing and accelerated return to activity. With appropriate indications and surgical technique, graft survival following OCA transplantation can exceed 90% at 10 years postoperatively, allow for predictable (70%-80%) return to sport, and produce clinically meaningful improvements in patient-reported outcomes. Full return to sports is often possible between 4 and 10 months postoperatively. Careful attention to postoperative rehabilitation and strength progression prior to return to sport is imperative to prevent graft overload, joint inflammation, or secondary injury to other knee structures such as meniscus or ligamentous structures. This article reviews the overall indications, technique, and outcomes of OCA transplantation in the athletic population.

Acetabular Coverage May Affect Radiographic and Clinical Outcomes of Osteochondral Allograft Transplantation of Focal Femoral Head Lesions: A Case Series From a Single Institution.

Osteochondral lesions of the femoral head in young people are rare and present unique management challenges. Optimal treatment for these lesions is unclear. From 2009 to 2016, clinical and radiographic outcomes were prospectively collected within a series of symptomatic focal osteochondral lesions of the femoral head with a minimum follow-up of 2 years. A surgical hip dislocation followed by implantation of a size-matched fresh osteochondral femoral head allograft was performed. Nine hips in eight patients (6 female patients) underwent surgery at an average of 17 years (11 to 21 years). Individual allograft sizes ranged from 10 to 35 mm in diameter; with 2 of 9 hips receiving two allografts in a stacked or mosaicplasty technique at the time of treatment. The average graft implantation was 3536.5 mm2. Modified Harris hip scores improved by 13.4 (P = 0.018) from preoperative to final follow-up for all patients. Significant improvements in internal rotation (12° versus 23°, P = 0.011), external rotation (32° versus 50°, P = 0.041), and abduction (28° versus 40°, P = 0.042) were also achieved. Three patients (four hips) demonstrated poor radiographic healing (<50% incorporation at 2 years), which correlated with worse clinical outcomes and was associated with a lower preoperative lateral center edge angle (21.5° versus 30.4°, P = 0.049). Fresh osteochondral allograft treatment is a good option for focal osteochondral lesions of the femoral head with improved outcomes and motion; however, higher failure rates may be seen in those with a lower center edge angle.

Which Variables Predict Osteochondral Allograft Failure?

Objectives:Osteochondral allograft (OCA) transplantation is a valuable treatment option for chondral and osteochondral lesions of the knee. Understanding the impact of clinical variables on the outcome of OCA transplantation would be useful for counseling patients on the relative risk of the procedure. The purpose of this study was to determine which variables predicted treatment failure in a large cohort of patients undergoing OCA transplantation of the knee.Methods:OCA transplantation was performed in 673 knees from 1997 to 2016; 489 had a minimum follow-up of two years. Average age was 32 years and 63% were male. Mean graft size was 8.9 cm2. Reoperations following the OCA transplantations were assessed, and treatment failure was defined as any procedure that involved removal of the allograft. Variables associated with treatment failure in univariate analyses (age, diagnosis, anatomic location, and graft size) were included in a logistic regression model.Results:Treatment failure occurred in 78 knees (16%); 58 conversions to arthroplasty, 19 revision allografting, and 1 patellectomy. Age, diagnosis, and graft size independently predicted a higher risk of failure (Table 1). Patients who were ≥30 years old were 2.4 times more likely than younger patients to experience a treatment failure. Compared to patients with osteochondritis dissecans or traumatic chondral injury, patients with degenerative chondral lesions, avascular necrosis, or osteoarthritis were more likely to have allograft failure. Grafts >8 cm2 were 2.1 times more likely to fail than grafts ≤8 cm2. Anatomic location and number of grafts were associated with failure in univariate analyses, but not after controlling for other variables in the multivariate analysis.Conclusion:Older age, diagnosis of avascular necrosis or degenerative joint disease, and larger graft size were associated with higher risk of treatment failure. This data is useful in counseling individual patients on the risk of osteochondral allograft surgery.Logistic regression analysis for variables predicting treatment failurePredictorReference groupOdds ratio in comparison to reference groupp-valueAge>30 years≤30 years 2.4 0.005 DiagnosisDCLOCD or TCI 2.4 0.026 FractureOCD or TCI3.20.064AVNOCD or TCI 4.2 0.002 OAOCD or TCI 5.2 0.001 Total graft size>8cm2≤8cm2 2.1 0.027 Significant findings (p<0.05) are shown in bold.DCL, degenerative chondral lesion; OCD, osteochondritis dissecans; TCI, traumatic chondral injury; AVN, avascular necrosis; OA, osteoarthritis; TP, tibial plateau; FC, femoral condyle.

One-Year MRI Outcomes of Osteochondral Allograft Transplantation of the Knee for Large Chondral Defects: Comparison of Elliptical, Stacked, and Single Allografts

Objectives:Osteochondral allograft transplantation (OCA) is a proven cartilage restoration procedure for patients with large chondral defects. However, elongated condylar lesions pose a challenge for dowel OCA in restoring articular surface congruity. Recently, instrumentation to harvest a single, elliptical allograft has been developed for treating ovoid lesions without requiring an adjacent-plug (stacked or snowman) technique. The purpose of this study was to compare 1-year MRI outcomes of patients treated with elliptical, stacked, or single OCA using the Osteochondral Allograft MRI Scoring System (OCAMRISS) and percent osseous integration.Methods:A retrospective review on patients treated from 2000 to 2018 with OCA for condylar defects of the knee was conducted. Inclusion criteria included those followed prospectively with a MRI at ˜1 year after surgery. OCAMRISS and osseous integration scores (0-25%; 26-50%; 51-75%; 76%-100%) were graded by a musculoskeletal radiologist blinded to the outcomes. Comparisons of demographics and MRI scores were performed with the ANOVA.Results:A total of 57 knees (mean age, 35.8 years; 70% male) met the inclusion criteria and were treated with either elliptical (n=19), stacked (n=19), or single (n=19) OCA. Mean time to post-operative MRI was 10.7, 11.1, and 12.4 months, respectively (p=0.17). There were no significant differences in demographics or number of prior ipsilateral knee surgeries among groups. Defect characteristics were significantly different between groups, where single plugs treated a higher percentage of LFC defects (58%) compared to elliptical and stacked (26%, each) (p=0.02). Total chondral defect area was greatest in the stacked group (5.4 ± 1.3) compared to elliptical (4.6 ± 1.2) and single (4.6 ± 1.4) (p=0.12). Bone, cartilage, ancillary, and total OCAMRISS scores were not significantly different between groups. A trend towards a higher percentage of osseous integration (single>stacked>elliptical) was noted which correlated with less transplanted allograft bone, however, these differences were not significant (p=0.15).Conclusion:One-year OCAMRISS and osseous integration scores did not differ among patients treated with elliptical, stacked, or single OCA. Further investigation is needed to explore potential differences in clinical outcomes and long-term osseous integration between elliptical and stacked OCA for the treatment of elongated condylar defects of the knee.Table 1.Patient Demographics, Intraoperative Data, and OCAMRISS Scores at 1-year Postoperative MRI Elliptical (n = 19) Stacked (n = 19) Single (n = 19) P Value Patient CharacteristicsAge, y37.0 ± 13.937.5 ± 11.133.1 ± 11.80.48Sex (male/female), n14/513/613/60.92Body mass index, kg/m2 25.7 ± 2.826.5 ± 5.025.9 ± 3.20.78No. of prior ipsilateral knee surgeries1.1 ± 1.41.9 ± 2.41.4 ± 0.80.29MRI follow-up, mo10.7 ± 3.911.1 ± 1.912.4 ± 2.20.17Lesion CharacteristicsOCA location, n (%)0.02Medial femoral condyle14 (74)14 (74)8 (42)Lateral femoral condyle5 (26)5 (26)11 (58)Total chondral defect area, cm2 4.6 ± 1.25.4 ± 1.34.6 ± 1.40.12OCAMRISS ScoreCartilage features3.5 ± 1.52.9 ± 1.53.4 ± 2.10.48Bone features3.0 ± 0.72.7 ± 0.72.8 ± 0.60.30Ancillary features3.0 ± 1.12.9 ± 1.02.6 ± 1.10.46Total9.5 ± 2.18.4 ± 2.58.8 ± 3.10.45Osseous Integration Score2.1 ± 1.11.7 ± 0.901.5 ± 0.600.15

Does Anterior Cruciate Ligament Reconstruction Affect the Outcome of Osteochondral Allograft Transplantation? A Matched Cohort Study With a Mean Follow-up of 6 Years

Background: Few studies have evaluated the influence of anterior cruciate ligament (ACL) reconstruction on the outcome of cartilage repair. Hypothesis/Purpose: The purpose was to investigate the association between ACL reconstruction and functional outcomes after osteochondral allograft (OCA) transplantation. The hypothesis was that patients treated with OCA transplantation who had a history of ACL reconstruction would have inferior clinical outcomes and lower osteochondral graft survivorship when compared with a matched group of patients undergoing OCA transplantation without a history of ACL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: This study compared 31 knees that underwent OCA transplantation with a history of ACL reconstruction (OCA and ACL group) and 62 knees treated with isolated OCA transplantation (OCA group) that had an intact ACL. Groups were matched by age, diagnosis, year of surgery, and graft size. Minimum follow-up was 2 years. Frequency and type of reoperation were assessed. Clinical failure was defined as revision OCA transplantation or conversion to arthroplasty. Subjective outcome measures included International Knee Documentation Committee scores, Knee injury and Osteoarthritis Outcome Scores, and patient satisfaction. Results: Clinical failure occurred in 3 of 31 knees (9.7%) in the OCA and ACL group and 6 of 62 knees (9.7%) in the OCA group (P ≤ .999). Five- and 10-year survivorship of the OCA was 94.7% and 82.3% for the OCA and ACL group and 93.4% and 79.6% for OCA group, respectively (P = .979). Mean follow-up was 6.2 ± 3.3 years among all knees with grafts in situ. Changes from preoperative to latest follow-up visit (difference scores) on all subjective outcome measures were greater in the OCA group; however, none of the difference scores were statistically significant. Satisfaction with the results of OCA transplantation was reported in 78.3% of the OCA and ACL group and 71.7% of the OCA group (P = .551). Conclusion: Treatment of cartilage lesions with OCA transplantation proved to be reliable and effective regardless of a history of ACL reconstruction as demonstrated by the improvements in outcome scores, long survivorship, and high satisfaction rates. History of ACL reconstruction did not influence outcome of OCA transplantation.

Clinical Outcomes of Osteochondral Allograft Transplantation for Secondary Treatment of Osteochondritis Dissecans of the Knee in Skeletally Mature Patients

To report clinical outcomes of osteochondral allograft transplantation (OCA) for skeletally mature patients with osteochondritis dissecans (OCD) lesions of the knee in whom prior surgical intervention has failed, and to describe return-to-sport (RTS) rates and any predictive demographic or preoperative variables associated with a higher likelihood to RTS. Patients who underwent OCA by a single surgeon (B.J.C.) between October 1, 2002, and November 30, 2014, for a diagnosis of OCD with a minimum of 2years' follow-up were included. Demographic, surgical history, operative, and postoperative data points including RTS were analyzed for all patients collectively, with subanalysis to identify any demographic and operative variables associated with the ability to RTS. Failure was defined as revision OCA, gross appearance of graft failure on second-look arthroscopy, or conversion to arthroplasty. We identified 41 consecutive patients (43 knees), with 37 patients (39 knees, comprising 26 male and 13 female knees) available for clinical follow-up at an average of 7.29 ± 3.30years. There was significant improvement (P < .05) in all patient-reported outcome scores, with the exception of the Short Form 12 mental subscale (P= .910). Most patients (81.6%) reported being either mostly satisfied or completely satisfied at final follow-up. Of patients self-identifying as athletes preoperatively (n= 22), 18 (81.8%) achieved RTS at an average of 14.0 ± 8.7months. Athletes with failure to RTS had a significantly greater body mass index (RTS, 24.68 ± 3.67; no RTS, 27.82 ± 0.69; P= .005). Subsequent surgery was performed in 14 patients (35.9%), and primary OCA failed in 2 patients at an average of 6.2 ± 3.8years. OCA is a successful secondary surgical treatment for OCD of the knee in skeletally mature patients and leads to clinically meaningful improvements in patient-reported outcome scores and high patient satisfaction and RTS rates in low-level athletes at an average of 7.29years' follow-up. Athletes with failure to RTS were found to have a significantly higher body mass index. Although reoperation may be common after OCA (35.9%), the failure rate is low (5.1%) in this series. Level IV, case series.

Osteochondral Allograft Transplantation of the Knee in Patients Aged 40 Years and Older

Background: Treatment of large chondral defects of the knee among patients aged ≥40 years remains a difficult clinical challenge owing to preexisting joint degeneration and the lack of treatment options short of arthroplasty. Purpose: To characterize the survivorship, predictors of failure, and clinical outcomes of osteochondral allograft transplantation (OCA) of the knee among patients aged ≥40 years. Study Design: Case series; Level of evidence, 4. Methods: Prospectively collected data were reviewed for 54 consecutive patients aged ≥40 years who were treated with OCA. Preoperative levels of osteoarthritis (according to Kellgren-Lawrence classification) and meniscal volume and quality were graded from review of radiographs and magnetic resonance imaging. Complications, reoperations, and patient responses to validated outcome measures were reviewed. A minimum follow-up of 2 years was required for analysis. Failure was defined by any removal or revision of the allograft or conversion to arthroplasty. Results: Among 51 patients (mean age, 48 years; range, 40-63 years; 65% male), a total of 52 knees had symptomatic focal cartilage lesions (up to 2 affected areas) that were classified as Outerbridge grade 4 at the time of OCA and did not involve substantial bone loss requiring shell allografts or additional bone grafting. Mean duration of follow-up was 3.6 years (range, 2-11 years). After OCA, 21 knees (40%) underwent reoperation, including 14 failures (27%) consisting of revision OCA (n = 1), unicompartmental knee arthroplasty (n = 5), and total knee arthroplasty (n = 8). Mean time to failure was 33 months, and 2- and 4-year survivorship rates were 88% and 73%, respectively. Male sex (hazard ratio = 4.18, 95% CI = 1.12-27.13) and a higher number of previous ipsilateral knee operations (hazard ratio = 1.70 per increase in 1 surgical procedure, 95% CI = 1.03-2.83) were predictors of failure. A higher Kellgren-Lawrence osteoarthritis grade on preoperative radiographs was associated with higher failure rates in the Kaplan-Meier analysis but not the multivariate model. At final follow-up, clinically significant improvements were noted in the pain (mean score, 47.8 to 67.6) and physical functioning (56.8 to 79.1) subscales of the Short Form-36, as well as the International Knee Documentation Committee subjective form (45.0 to 63.6), Knee Outcome Survey–Activities of Daily Living (64.5 to 80.1), and overall condition statement (4.5 to 6.8) (P < .001). No significant changes were noted for the Marx Activity Rating Scale (5.1 to 3.9, P = .789). Conclusion: A higher failure rate was found in this series of patients aged ≥40 years who were treated with OCA as compared with other studies of younger populations. However, for select older patients, OCA can be a good midterm treatment option for cartilage defects of the knee.

Do Outcomes of Osteochondral Allograft Transplantation Differ Based on Age and Sex? A Comparative Matched Group Analysis

Background: The effect of patient age or sex on outcomes after osteochondral allograft transplantation (OCA) has not been assessed. Purpose: To determine clinical outcomes for male and female patients aged ≥40 years undergoing OCA compared with a group of patients aged <40 years. Study Design: Cohort study; Level of evidence, 3. Methods: A review of prospectively collected data of consecutive patients who underwent OCA by a single surgeon with a minimum follow-up of 2 years was conducted. The reoperation rate, failure rate, and patient-reported outcome scores were reviewed. All outcomes were compared between patients aged <40 or ≥40 years, with subgroup analyses conducted based on patient sex. Failure was defined as revision OCA, conversion to knee arthroplasty, or gross appearance of graft failure at second-look arthroscopic surgery. Descriptive statistics, Fisher exact or chi-square testing, and Mann-Whitney U testing were performed, with P < .05 set as significant. Results: A total of 170 patients (of 212 eligible patients; 80.2% follow-up) who underwent OCA with a mean follow-up of 5.0 ± 2.7 years (range, 2.0-15.1 years) were included, with 115 patients aged <40 years (mean age, 27.6 ± 7.3 years; 58 male, 57 female) and 55 patients aged ≥40 years (mean age, 44.9 ± 4.0 years; 33 male, 22 female). There were no differences in the number of pre-OCA procedures between the groups (P = .085). There were no differences in the reoperation rate (<40 years: 38%; ≥40 years: 36%; P = .867), time to reoperation (<40 years: 2.12 ± 1.90 years; ≥40 years: 3.43 ± 3.43 years; P = .126), or failure rate (<40 years: 13%; ≥40 years: 16%; P = .639) between the older and younger groups. Patients in both groups demonstrated significant improvement in Lysholm (both: P < .001), International Knee Documentation Committee (IKDC) (both: P < .001), Knee Injury and Osteoarthritis Outcome Score (KOOS) (both: P < .001), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (both: P < .001), and Short Form–12 (SF-12) physical (both: P < .001) scores compared with preoperative values. Patients aged ≥40 years demonstrated significantly higher KOOS symptom (P = .015) subscores compared with patients aged <40 years. There were no significant differences in the number of complications, outcome scores, or time to failure between the sexes. In patients aged <40 years, female patients experienced failure significantly more quickly than male patients (P = .039). In contrast, in patients aged ≥40 years, male patients experienced failure significantly more quickly than female patients (P = .046). Conclusion: This study provides evidence that OCA is a safe and reliable treatment option for osteochondral defects in patients aged ≥40 years. Male and female patients had similar outcomes. Patients aged <40 years demonstrated lower KOOS symptom subscores postoperatively compared with older patients, potentially attributable to higher expectations of return to function postoperatively as compared with older patients.

Condyle-Specific Matching Does Not Improve Midterm Clinical Outcomes of Osteochondral Allograft Transplantation in the Knee.

Condyle-specific matching for osteochondral allograft transplantation (OCA) pairs donor and recipient condyles in an attempt to minimize articular incongruity. While the majority of cartilage defects are located on the medial femoral condyle, lateral femoral condyles are more commonly available as a graft source. The purpose of this study was to compare the clinical outcomes of patients treated with non-orthotopic (lateral-to-medial condyle or medial-to-lateral condyle) OCA with those treated with traditional orthotopic (medial-to-medial condyle or lateral-to-lateral condyle) OCA. We hypothesized that clinical outcomes would be similar between groups at midterm follow-up. A retrospective review of prospectively collected data on patients treated with OCA from 2000 to 2014 was conducted. Seventy-seven patients with a full-thickness cartilage defect of a femoral condyle were treated with either orthotopic (n = 50) or non-orthotopic (n = 27) OCA. A minimum follow-up of 2 years was required for analysis. Patients in each group were matched according to sex, age, and total chondral defect size. Reoperations and patient responses to validated outcome measures were reviewed. Failure was defined as any revision cartilage procedure or conversion to knee arthroplasty. The mean duration of follow-up was 4.0 years (range, 2 to 16 years). The orthotopic and non-orthotopic OCA groups were comparable in terms of demographics, the mean number of prior ipsilateral knee operations, and the percentage of concomitant procedures at baseline. Reoperation (p = 0.427) and failure (p = 0.917) rates did not differ significantly between groups. Both groups demonstrated significant increases in the Short Form-36 (SF-36) physical functioning and pain, International Knee Documentation Committee (IKDC), and Knee Outcome Survey-Activities of Daily Living (KOS-ADL) scores compared with baseline (p < 0.004). Outcome scores (baseline and postoperative) and change scores did not differ significantly between groups. Clinical outcomes do not differ between patients treated with orthotopic OCA and those treated with non-orthotopic OCA, suggesting that condyle-specific matching may not be necessary. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Similar Outcomes After Osteochondral Allograft Transplantation in Anterior Cruciate Ligament-Intact and -Reconstructed Knees: A Comparative Matched-Group Analysis With Minimum 2-Year Follow-Up

To compare failure rates and clinical outcomes of osteochondral allograft transplantation (OCA) in anterior cruciate ligament (ACL)-intact versus ACL-reconstructed knees at midterm follow-up. After a priori power analysis, a prospective registry of patients treated with OCA for focal chondral lesions ≥2cm2 in size with minimum 2-year follow-up was used to match ACL-reconstructed knees with ACL-intact knees by age, sex, and primary chondral defect location. Exclusion criteria included meniscus transplantation, realignment osteotomy, or other ligamentous injury. Complications, reoperations, and patient responses to validated outcome measures were reviewed. Failure was defined by any procedure involving allograft removal/revision or conversion to arthroplasty. Kaplan-Meier analysis and multivariate Cox regression were performed to evaluate the association of ACL reconstruction (ACLR) with failure. A total of 50 ACL-intact and 25 ACL-reconstructed (18 prior, 7 concomitant) OCA patients were analyzed. The mean age was 36.2years (range, 14-62years). Mean follow-up was 3.9years (range, 2-14years). Patient demographics and chondral lesion characteristics were similar between groups. ACL-reconstructed patients averaged 2.2 ± 1.9 prior surgeries on the ipsilateral knee compared with 1.4 ± 1.4 surgeries for ACL-intact patients (P= .014). Grafts used for the last ACLR included bone-patellar tendon-bone autograft, hamstring autograft, Achilles tendon allograft, and tibialis allograft (data available for only 11 of 25 patients). At final follow-up, 22% of ACL-intact and 32% of ACL-reconstructed patients had undergone reoperation. OCA survivorship was 90% and 96% at 2years and 79% and 85% at 5years in ACL-intact and ACL-reconstructed patients, respectively (P= .774). ACLR was not independently associated with failure. Both groups demonstrated clinically significant improvements in the Short Form-36 pain and physical functioning, International Knee Documentation Committee subjective, and Knee Outcome Survey-Activities of Daily Living scores at final follow-up (P<.001), with no significant differences in preoperative, postoperative, and change scores between groups. OCA in the setting of prior or concomitant ACLR does not portend higher failure rates or compromise clinical outcomes. Level III, retrospective comparative study.

Do Outcomes of Osteochondral Allograft Transplantation Differ Based on Patient Sex: A Comparative Matched Group Analysis of Male and Female Patients

Objectives:Osteochondral allograft transplantation (OAT) is being performed with increasing frequency, though to date, the impact of patient sex on outcomes and failure rates has not been assessed. The purpose of this study was to determine clinical outcomes for male versus female patients undergoing OAT.Methods:A retrospective review of prospectively collected data of patients who underwent OAT by a single surgeon with a minimum follow-up of 2 years was conducted. Males who underwent OAT were compared to a matched group of females who underwent OAT (age ± 3 years, gender, BMI ± 5 kg/m2, the presence of previous ipsilateral knee surgeries, and the presence of meniscal transplantation). The reoperation rate, failure rate, timing of reoperation, procedures performed, findings at surgery, and patient reported outcome scores were reviewed. Failure was defined by revision OAT, conversion to knee arthroplasty, or gross appearance of graft failure at 2nd look arthroscopy. Descriptive statistics, fisher’s exact or chi-square testing, and Mann-Whitney U testing were performed, with P<0.05 set as significant.Results:A total of 98 patients (average age 32.1±9.9 years, 49 males, 49 females) who underwent OAT with an average follow-up of 4.7±2.33 years (range, 2.1-12.1) were included. These patients underwent an average of 2.6±1.8 prior surgical procedures on the ipsilateral knee prior to OAT. A total of 33 patients underwent reoperation at an average 2.4±2.4 years, with 27% (9/33) undergoing additional reoperations (range, 1-2 additional reoperations). Male patients did not have significantly different reoperation rates (42% vs. 27%), time to reoperation (2.50±2.12 vs. 2.29±1.71 years) or failure rates (20% vs. 8%) compared to female patients (P>0.05 for all). Both male and female patients showed significant improvement in Lysholm, IKCD, KOOS, WOMAC, and SF-12 physical subscale as compared to preoperative values (P>0.05 for all for both groups). The SF-12 mental subscale was not significantly improved at final follow-up for either group (P>0.05). There were no significant differences in patient reported outcomes scores at most recent follow-up when comparing males and females. Males demonstrated significantly larger defect areas compared to females (371.65±168.89 vs. 310.63±117.15 mm2, P=0.037), though the defect:condyle ratio was not significantly different (male: 0.19 vs. female: 0.20, P>0.05).Conclusion:Males and females have similar clinical outcomes at 5 years following OAT, though males trended toward increased reoperation rates and increased failure rates. This data implies that overall, similar favorable outcomes may be expected for patients regardless of sex, with an 86% graft survival rate at 5 years. This information can be used to counsel patients when being offered OAT as part of a knee joint preservation strategy.

Do Outcomes of Osteochondral Allograft Transplantation Differ Based on Age

Objectives:Osteochondral allograft transplantation (OAT) is being performed with increasing frequency, though to date, the impact of patient age on outcomes and failure rates has not been assessed. The purpose of this study was to determine clinical outcomes for patients over 40 years of age undergoing OAT compared to a cohort of patients under 40.Methods:A review of prospectively collected data of patients who underwent OAT by a single surgeon with a minimum follow-up of 2 years was conducted. Patients <40 or ≥40 years were grouped. The reoperation rate, failure rate, timing of reoperation, procedures performed, findings at surgery, and patient reported outcome scores were reviewed. Failure was defined by revision OAT, conversion to knee arthroplasty, or gross appearance of graft failure at 2nd look arthroscopy. Descriptive statistics, fisher’s exact or chi-square testing, and Mann-Whitney U testing were performed, with P<0.05 set as significant.Results:A total of 170 patients who underwent OAT with an average follow-up of 5.0±2.7 years (range, 2.0-15.1) were included; 115 patients <40 years (average age 27.6±7.31 years, 58 males, 57 females) and 55 patients ≥40 years (average age 44.9±4.0 years, 33 males, 22 females). There were no differences detected in the number of pre-OAT surgeries between the groups (<40: 2.70±1.91; ≥40: 2.13±1.04; P=0.085). The ≥40 patients demonstrated significantly higher BMI (<40: 25.94±5.02 kg/m2; ≥40: 28.11±5.22 kg/m2; P=0.018), higher prevalence of workers’ compensation patients (<40: 17%; ≥40: 33%; P=0.028), and lower prevalence of concomitant distal femoral osteotomy (<40: 8%; ≥40: 0%; P=0.028). There were no differences detected in reoperation rate (<40: 38%; ≥40: 36%; P=0.867), time to reoperation (<40: 2.12±1.90; ≥40: 3.43±3.43; P=0.126), or failure rate (<40: 13%; ≥40: 16%; P=0.639) between each group. Patients in both groups demonstrated significant improvement in Lysholm, IKCD, KOOS, WOMAC, and SF-12 physical subscale as compared to preoperative values (P>0.05 for all for both groups). The SF-12 mental subscale was not significantly improved at final follow-up for either group. The older group demonstrated significantly higher Lysholm (P=0.045) and KOOS-sport (P=0.015) scores compared to the younger group at final recent follow-up. There were no other significant differences in patient reported outcomes scores, other concomitant surgeries, or defect sizes.Conclusion:Patients ≥40 years of age undergoing OAT have similar survival and reoperation rates at 5 years following surgery compared to younger patients. The <40 patients demonstrated lower Lysholm and KOOS-sport scores, potentially attributable to higher expectations of return to function post-operatively as compared to older patients. This information can be used to counsel patients when being offered OAT as part of a knee joint preservation strategy.

Surgical dislocation of the adult hip

Surgical dislocation of the hip is rarely undertaken. The potential danger to the vascularity of the femoral head has been emphasised, but there is little information as to how this danger can be avoided. We describe a technique for operative dislocation of the hip, based on detailed anatomical studies of the blood supply. It combines aspects of approaches which have been reported previously and consists of an anterior dislocation through a posterior approach with a 'trochanteric flip' osteotomy. The external rotator muscles are not divided and the medial femoral circumflex artery is protected by the intact obturator externus. We report our experience using this approach in 213 hips over a period of seven years and include 19 patients who underwent simultaneous intertrochanteric osteotomy. The perfusion of the femoral head was verified intraoperatively and, to date, none has subsequently developed avascular necrosis. There is little morbidity associated with the technique and it allows the treatment of a variety of conditions, which may not respond well to other methods including arthroscopy. Surgical dislocation gives new insight into the pathogenesis of some hip disorders and the possibility of preserving the hip with techniques such as transplantation of cartilage.