Evaluation of Knee Donor and Elbow Recipient Sites for Osteochondral Autologous Transplantation Surgery in Capitellar Osteochondritis Dissecans

Surgical approaches to the capitellum: a comparative anatomic study

BACKGROUND

Osteochondritis dissecans (OCD) of the humeral capitellum is an important cause of elbow disability in young athletes. Large and unstable lesions sometimes require joint reconstruction with osteochondral autograft. Several approaches have been described to expose the capitellum for the purpose of treating OCD. The posterior anconeus-splitting approach and the lateral approach with or without release of the lateral ligamentous complex are the most frequently used for this indication. The surface accessible by these approaches has not been widely studied. This study compared the extent of the articular surface of the capitellum that could be exposed with the Kocher approach (without ligament release) vs. the posterior anconeus-splitting approach. A secondary outcome was the measurement of any additional area that could be reached with lateral ulnar collateral ligament release (Wrightington approach).

METHODS

The 3 approaches were performed on 8 adult cadaveric elbows: first, the Kocher approach; then, the anconeus-splitting approach; and finally, the Wrightington approach. The visible articular surface was marked out after completion of each approach.

RESULTS

The mean articular surface of the capitellum was 708 mm2 (range, 573-830 mm2). The mean visible articular surface was 49% (range, 43%-60%) of the total surface with the Kocher approach, 74% (range, 61%-90%) with the posterior anconeus-splitting approach, and 93% (range, 91%-97%) with the Wrightington approach. Although the Kocher approach provided access to the anterior part of the capitellum, the anconeus-splitting approach showed adequate exposure to the posterior three-quarters of the articular surface and overlapped the most posterior part of the Kocher approach. A combination of the 2 lateral ulnar collateral ligament-preserving approaches allowed access to 100% of the joint surface.

CONCLUSION

Most OCD lesions are located in the posterior area of the capitellum and can therefore be reached with the anconeus-splitting approach. When OCD lesions are located anteriorly, the Kocher approach without ligament release is efficient. A combination of these 2 approaches enabled the entirety of the joint surface to be viewed.

Osteochondritis dissecans of the metacarpal head in a soldier treated with osteochondral autograft transplantation surgery: A case report

RATIONALE

Osteochondral autograft transplantation surgery (OATS) was introduced as a treatment for hand osteochondritis dissecans (OCD), and successful results were reported. However, the cartilage height of the donor plug has not yet been established compared with that of other joints. We present a case using OATS for OCD of the 3rd metacarpal (MCP) head that occurred in a soldier and the findings of magnetic resonance imaging (MRI) images taken at 12 weeks after surgery.

PATIENT CONCERNS

A 21-year-old male presented with a painful, swollen 3rd MCP joint in the right hand. He was a soldier and right-handed; in addition, he did not recall any traumatic events, nor had he taken any corticosteroid medications before. The patient was excluded from military training and underwent conservative treatment with medication and a brace in a military hospital for 3 months.

DIAGNOSIS

The patient was diagnosed with OCD due to avascular necrosis of the 3rd MCP head of the right hand through X-ray and MRI.

INTERVENTIONS

OATS was planned as a surgical treatment. Surgery uncovered a 10 × 10 mm2, isolated cartilage defect of the 3rd MCP head that had an irregular margin and a loose body. Using Arthrex OATS, a 10-mm diameter, 10-mm depth hole was made at the articular defect site, and an 11-mm diameter, 12-length plug was harvested from the left lateral femoral condyle. The donor plug was inserted into the prepared defect site with press-fit fixation.

OUTCOMES

At the last follow-up, the height of the articular cartilage had subsided with union on MRI 12 weeks after the surgery. However, the patient was asymptomatic with a normal range of motion of the right hand, and he returned to military training.

LESSONS

Although the joints of the hand are small and non-weight bearing, the level of articular cartilage of the donor plug was subsided in a follow-up MRI in our case. We suggest that the difference in cartilage thickness between the donor and the recipient might have been the cause of subsidence of the articular cartilage, and therefore, it may be helpful to transplant donors with similar thicknesses of articular cartilage.

A Quantitative Analysis of Subchondral Bone Density Around Osteochondritis Dissecans Lesions of the Capitellum

PURPOSE

In capitellar osteochondritis dissecans (OCD), unstable lesions generally demonstrate signs of subchondral sclerosis. We postulate that OCD lesions have abnormal subchondral bone density. We aimed to quantify the subchondral bone thickness around OCD lesions using conventional computed tomography (CT) imaging.

METHODS

This retrospective study included 15 patients with capitellar OCD (OCD group) and 12 patients with an unaffected radio-capitellar joint (control group). We constructed 3-dimensional humerus models using CT data and quantified the bone density with colored contour mapping to determine the subchondral bone thickness. We measured the thickness relative to the condylar height at the centroid and lateral, medial, superior, and inferior edge points of the OCD lesion, and compared the findings between the groups. We then correlated the CT measurements with the magnetic resonance imaging measurements.

RESULTS

Subchondral bone thickness at the centroid and lateral, medial, superior, and inferior edges in the OCD group was significantly higher than that in the control group. Correlation analyses revealed that the magnetic resonance imaging measurements highly correlated with the CT subchondral bone measurements.

CONCLUSIONS

We found that there is a zone of increased subchondral bone thickness around OCD lesions that should be considered during drilling, microfracture, or other reconstruction methods. We observed a high correlation with low errors between the measurements taken from conventional CT images and the measurements from magnetic resonance imaging, suggesting that both modalities are useful in clinical decision making.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Fresh Precut Osteochondral Allograft Core Transplantation for the Treatment of Capitellum Osteochondritis Dissecans

Osteochondritis dissecans (OCD) of the elbow is a disease of unclear etiology that affects young children and adolescents, particularly overhead athletes and gymnasts. Common surgical options include fixation, debridement, loose body removal, and marrow stimulation (microfracture/drilling). For large, deep, and/or uncontained defects, osteochondral autograft transplantation (OAT) has been advocated. However, there are some drawbacks to OAT, particularly related to donor-site morbidity. Fresh osteochondral allograft (OCA) transplantation avoids the donor-site morbidity associated with OAT and has been shown to be effective for treating capitellar OCD. This Technical Note details a surgical technique of OCA transplantation of the capitellum in an adolescent patient using a fresh precut OCA core. This procedure addresses the cartilage defect and loss of subchondral bone associated with OCD without the drawbacks associated with harvesting an autograft. Furthermore, as the graft is readily available, it avoids delays related to the donor-recipient matching process.

Early Radiographic Healing and Functional Results After Autologous Osteochondral Grafting for Osteochondritis Dissecans of the Capitellum: Introduction of a New Magnetic Resonance Imaging-Based Scoring System

BACKGROUND

Autologous osteochondral grafting (OG) is an option in the treatment of capitellar osteochondritis dissecans (COCD). However, radiographic healing after this procedure has not been well documented.

PURPOSE

To develop a magnetic resonance imaging (MRI)-based scoring system specific for evaluating healing after single-plug OG in COCD and to evaluate correlation between radiographic healing and early clinical outcomes.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

Between 2014 and 2017, 183 elbows with COCD were enrolled in a prospective registry. A total of 61 elbows in 59 patients underwent single-plug OG. Of these, 52 elbows in 50 patients had pre- and postoperative MRI scans. Postoperative MRI and clinical outcome data from this group were used to develop the novel BOGIE score (Boston Osteochondral Graft Incorporation in the Elbow), with a possible range of 4 to 12.

RESULTS

Median age at surgery was 14.2 years (interquartile range, 13.1-15.0 years). Median clinical follow-up after OG was 12.4 months (interquartile range, 9.5-16.9 months; range, 6-53 months). Compared with before surgery, elbow function at 6 months after surgery and at latest follow-up was significantly improved as measured by the Timmerman and Andrews score (TAS; median: 145 before surgery, 185 at 6 months after surgery, 190 at latest follow-up; P < .001, before vs after surgery), as well as the short version of Disabilities of the Arm, Shoulder and Hand score; median: 21 before surgery, 7 at 6 months after surgery, and 0 at latest follow-up; P < .001 before surgery vs after surgery). Median BOGIE score at 6 months after surgery was 10 (range, 4-12). BOGIE score intraobserver reliability was 0.90 (95% CI, 0.82-0.94) for reader 1 and 0.91 (95% CI, 0.86-0.95) for reader 2. Interobserver reliability between the readers was 0.86 (95% CI, 0.78-0.92). Correlation was observed between the 6-month BOGIE score and the concurrent postoperative objective TAS (P < .001) as well as total TAS (P = .01) but not the subjective TAS (P = .08). Patients who underwent subsequent secondary surgery for persistent symptoms had a significantly lower postoperative BOGIE score at 6 months than those who did not (median, 7.8 vs 10.3; P = .016).

CONCLUSION

Quantitative evaluation for radiologic healing after single-plug OG in COCD is possible. The MRI-based BOGIE score appears to correlate with early clinical function and may be useful as an adjunct tool in decision making on activity progression. The use of a standardized MRI score may improve comparability of outcomes after OG in the literature.

Histologic Analysis of 2 Alternative Donor Sites of the Ipsilateral Elbow in the Treatment of Capitellar Osteochondritis Dissecans

PURPOSE

To compare the histologic features of the cartilage from the capitellum with 2 proposed alternative donor sites from the ipsilateral elbow in the treatment of capitellar osteochondritis dissecans (OCD): the nonarticulating part of the radial head and the nonarticulating lateral side of the olecranon tip.

METHODS

Ten human cadaveric elbow specimens with macroscopically normal articular surfaces were used to obtain 5-mm osteochondral grafts: 10 from the capitellum (60° anteriorly relative to the humeral shaft), 10 from the radial head (nonarticulating part at 80°), and 4 from the olecranon (lateral side of the olecranon tip). Grafts were fixated in formalin (4% formaldehyde), decalcified, and processed into standard 8-μm-thick hematoxylin and eosin-and Toluidine Blue-stained sections. These were assessed for cartilage thickness, shape of articular surface, and 13 histologic parameters of the International Cartilage Repair Society II. Olecranon scores were excluded from statistical analysis.

RESULTS

Mean cartilage thickness was 1.5 ± 0.22 mm at the capitellum; 1.3 ± 0.34 mm at the radial head; and 1.9 ± 1.0 mm at the olecranon. There was no difference in cartilage thickness between the capitellum and radial head (P = .062). All grafts demonstrated a convex articular surface. International Cartilage Repair Society II scores ranged from 82 to 100 for the capitellum, from 81 to 100 for the radial head, and from 67 to 87 for the olecranon tip. There was less chondrocyte clustering at the capitellum (84 ± 14) than in the radial head (94 ± 3.2; P = .019). Mid/deep zone assessment of the capitellum scored higher (97 ± 6.7) than the radial head (91 ± 4.6; P = .038).

CONCLUSIONS

This study demonstrates appropriate histologic similarities between the cartilage from the capitellum and 2 alternative donor sites of the ipsilateral elbow in the treatment of capitellar OCD: the nonarticulating part of the radial head and the nonarticulating lateral side of the olecranon tip.

CLINICAL RELEVANCE

From an histologic point of view, there seem to be no obstacles to use grafts from these alternative donor sites for reconstruction of the capitellum when performing osteochondral autologous transplantation.

Regional Distribution of Articular Cartilage Thickness in the Elbow Joint: A 3-Dimensional Study in Elderly Humans

During elbow procedures, reconstruction of the joint (including the articular cartilage) is important in order to restore elbow function; however, the regional distribution of elbow cartilage is not completely understood. The purpose of the present study was to investigate the 3-dimensional (3-D) distribution patterns of cartilage thickness of elbow bones (including the distal part of the humerus, proximal part of the ulna, and radial head) in order to elucidate the morphological relationship among them.

Osteochondritis dissecans lesions of the capitellum in overhead athletes: a review of current evidence and proposed treatment algorithm

PURPOSE OF THE REVIEW

To review the most recent literature on osteochondritis dissecans (OCD) lesions of the capitellum in overhead athletes and describe a treatment algorithm based on current best evidence and surgeon experience.

RECENT FINDINGS

Recent research has included larger cohort studies with longer follow-up as well as quality systematic reviews and meta-analyses. These studies have focused on understanding how lesion characteristics such as size, location, and appearance on advanced imaging can predict treatment success. Current literature continues to support nonoperative management for stable lesions. Operative intervention is generally required for unstable lesions and treatment strategies are largely dictated by lesion size and location: debridement or reparative techniques for small lesions while larger lesions or those in high-stress locations are better served by bone and/or cartilage restoration procedures. There has been a rising interest in the use of allograft materials and cell-based therapies. Overhead athletes are uniquely predisposed to capitellar OCD due to the nature of forces applied to the radiocapitellar joint during repeated activity in the overhead position. Despite improvements in operative techniques, successful use of alternative graft materials, and a better understanding of how lesion characteristics influence results, there is still much to learn about this challenging disorder. Future research should focus on comparing operative techniques, refining their indications, and further developing a reliable treatment algorithm that best serves the overhead athlete.

Demographics and Epidemiology of Osteochondritis Dissecans of the Elbow Among Children and Adolescents

Background

Osteochondritis dissecans (OCD) of the elbow is a disorder of subchondral bone and articular cartilage, of which the incidence among children is not clearly known.

Purpose

To assess the demographics and epidemiology of OCD of the elbow among children.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A retrospective chart review of an integrated health system for the years 2007 through 2011 was performed for patients with elbow OCD aged 2 to 19 years. Lesion location, laterality, and all patient demographics were recorded. OCD incidence was determined for the group as a whole as well as by sex and age group (2-5, 6-11, 12-19 years). Patient differences based on age, sex, and ethnicity were analyzed, and multivariable logistic regression models were used to assess the risk of elbow OCD by group.

Results

A total of 37 patients with 40 OCD lesions fit the inclusion criteria. No lesion was found among 2- to 5-year-olds. A majority of lesions (n = 39, 97.5%) were in the capitellum, and 1 (2.5%) was in the trochlea. Twenty-five patients (67.6%) had right-sided lesions; 9 (24.3%), left-sided; and 3 (8.1%), bilateral. The incidence of elbow OCD for patients aged 6 to 19 years was 2.2 per 100,000 overall and 3.8 and 0.6 per 100,000 for males and females, respectively. The majority of OCD cases were seen in those aged 12 to 19 years, with an incidence of 3.4 per 100,000 versus 0.38 among 6- to 11-year-olds. Multivariable logistic regression analysis revealed a 21.7-times increased odds ratio of elbow OCD among patients aged 12 to 19 years versus 6 to 11 years, and males had a 6.8-times greater odds ratio of elbow OCD than females (P < .0001 for both). Based on race and ethnicity, non-Hispanic whites had the highest incidence of elbow OCD as compared with all other ethnic groups.

Conclusion

In this population-based cohort study of pediatric elbow OCD, males had almost 7 times the risk of elbow OCD as compared with females, and 12- to 19-year-olds had nearly 22 times the risk of elbow OCD versus 6- to 11-year-olds. In keeping with many prior studies, the majority of patients had right-sided lesions.

Location of Osteochondritis Dissecans Lesions of the Capitellum

PURPOSE

The location of capitellar osteochondritis dissecans (OCD) lesions in the sagittal plane guides the surgical approach, and lesion location in the coronal plane influences surgical management. Although most lesions have been reported to occur between 4 o'clock and 4:30 (120° to 135° anterior to the humerus), some lesions are located elsewhere in the capitellum. The primary aim was to define the region of the capitellum affected by OCD lesions using a novel clock-face localization system.

METHODS

We reviewed 104 magnetic resonance imaging examinations diagnosing a nontraumatic capitellar OCD lesion. In the sagittal plane, lesion margins were recorded as degrees on the capitellum and converted into a clock-face format in which 0° corresponds to 12:00 with the forearm facing to the right. The 0° axis (12-o'clock axis) was defined as a line parallel to the anterior humeral line that intersects the capitellum center. The following coronal measurements were recorded: lesion width, capitellar width, and distance between the lateral capitellum and lateral lesion. Two independent observers took measurements.

RESULTS

In the sagittal plane, average lesion location was 92° to 150° (3:04-5:00, clock face) and ranged from 52.1° to 249.5° (1:44-8:19, clock face). Average lesion dimensions were 10.7 mm (mediolateral width) and 5.2 mm (anteroposterior depth). Interrater reliability was high (intraclass correlation coefficient = 0.98).

CONCLUSIONS

Using a magnetic resonance imaging-based clock-face localization system, we found that capitellar OCD lesions affect a broad region of the capitellum in the sagittal plane.

CLINICAL RELEVANCE

The clock-face localization system allows for precise description of capitellar OCD lesion location, which may facilitate intraoperative decision and longitudinal monitoring.

A matched quantitative computed tomography analysis of 3 surgical approaches for osteochondral reconstruction of the capitellum

BACKGROUND

The location of capitellar osteochondritis dissecans (OCD) lesions in the sagittal plane guides the surgical approach used for autologous osteochondral transplantation. We sought to compare the capitellar region accessible for orthogonal graft placement through 3 approaches: (1) posterior anconeus-split approach; (2) lateral approach with lateral collateral ligament (LCL) preservation (LCL-preserving lateral approach); and (3) lateral approach with LCL release (LCL-sacrificing lateral approach).

METHODS

The 3 approaches were sequentially performed on 9 cadaveric elbows: posterior anconeus-split approach, LCL-preserving lateral approach, and LCL-releasing lateral approach. The extent of perpendicular access was delineated with Kirschner wires. Each specimen underwent computed tomography. The accessible region was quantified as degrees on the capitellum and converted into time on a clock, where 0° corresponds to the 12-o'clock position. Generalized estimating equation modeling was used to investigate for significant within-specimen, between-approach differences.

RESULTS

The LCL-preserving and LCL-sacrificing lateral approaches provided more anterior perpendicular access than the posterior anconeus-split approach (mean, 0° vs 83°; P < .001). The posterior anconeus-split approach provided more posterior perpendicular access (mean, 215.0°; P < .001) than the LCL-preserving (mean, 117°; P < .001) and LCL-sacrificing (mean, 145°; P < .001) lateral approaches. The LCL-sacrificing lateral approach provided more posterior exposure than the LCL-preserving lateral approach (mean, 145° vs 117°; P < .001). The mean arc of visualization was greater for the LCL-sacrificing lateral approach than for the LCL-preserving lateral approach (145° vs 117°, P < .001).

CONCLUSIONS

A capitellar OCD lesion can be perpendicularly accessed from a posterior anconeus-split approach if it is posterior to 83° (2:46 clock-face position). A laterally based approach may be required for lesions anterior to this threshold. These data inform clinical decisions regarding the appropriate surgical approach for any OCD lesion.

Topographic Analysis of 2 Alternative Donor Sites of the Ipsilateral Elbow in the Treatment of Capitellar Osteochondritis Dissecans

PURPOSE

To find the best topographic subchondral bone match between the capitellum and 2 proposed alternative donor sites of the ipsilateral elbow for capitellar osteochondral autologous transplantation: the non-articulating part of the radial head and the lateral olecranon tip.

METHODS

In our retrospective database, 20 patients with an unremarkable computed tomography scan of the elbow despite clinical suspicion were identified for analysis. Included were patients aged 11 to 20 years with intact osseous structures and a computed tomography slice thickness of 1.25 mm or less. Three-dimensional polygon models were created using a standard predefined threshold, after which 4 articular surface lesions on the capitellum were created: central 40°, central 60°, lateral 40°, and lateral 60°. In addition, 3 donor locations on the non-articulating part of the radial head (diameter, 5 mm) and the lateral olecranon tip (diameter, 3.5 mm) were created. For each of 24 donor-recipient combinations, the donor graft surface was virtually placed on the recipient surface to quantify the mean distance between surfaces.

RESULTS

The group of 20 patients consisted of 16 male and 4 female patients with a mean age of 15.9 years (range, 12-18 years). For a central 40° lesion, the mean distance across all 6 donor-recipient combinations ranged from 0.085 ± 0.023 to 0.118 ± 0.036 mm; for a central 60° lesion, the mean distance ranged from 0.075 ± 0.018 to 0.117 ± 0.062 mm; for a lateral 40° lesion, the mean distance ranged from 0.087 ± 0.030 to 0.182 ± 0.226 mm; and for a lateral 60° lesion, the mean distance ranged from 0.084 ± 0.048 to 0.115 ± 0.045 mm. There were no differences in topographic matching between donor-recipient combinations.

CONCLUSIONS

The findings of this study show a less than 0.2-mm difference in the topographic subchondral bone match between 4 common lesion locations on the capitellum and 2 alternative donor sites of the ipsilateral elbow for capitellar osteochondral autologous transplantation: the non-articulating part of the radial head and the lateral olecranon tip.

CLINICAL RELEVANCE

These findings suggest that the non-articulating part of the radial head and the lateral olecranon tip may potentially be used as a donor source when treating capitellar osteochondritis dissecans.

Costal Osteochondral Autograft for Advanced Osteochondritis Dissecans of the Humeral Capitellum in Adolescent and Young Adult Athletes: Clinical Outcomes with a Mean Follow-up of 4.8 Years

BACKGROUND

Costal osteochondral grafting is a technique to achieve anatomical and biological repair of articular defects. Some small series of clinical applications of this procedure for advanced osteochondritis dissecans of the humeral capitellum, with short-term follow-up, have been reported; however, longer-term outcomes remain unclear. The purpose of this study was to clarify longer-term clinical outcomes of costal osteochondral autografts in the treatment of advanced osteochondritis dissecans of the humeral capitellum.

METHODS

Seventy-two patients with an osteochondral defect of the humeral capitellum were treated with costal osteochondral autograft and followed for a minimum of 3 years (mean follow-up, 57 months; range, 36 to 147 months). The mean patient age was 14.3 years. Clinical outcomes, including elbow range of motion, Timmerman and Andrews clinical rating score, donor-site morbidity, responses to a questionnaire regarding a return to sporting activities, and radiographic findings, were evaluated.

RESULTS

The mean elbow range of extension/flexion increased significantly, from -21°/122° preoperatively to -4°/136° postoperatively (p < 0.001). The mean clinical rating score improved significantly, from 101 to 190 by the latest follow-up (p < 0.001). The overall clinical score-based assessment was excellent for 60 patients, good for 9, and fair for 3. Seventy of the 72 patients returned to their original sport. The remaining 2 patients had changed sporting activities before surgery and did not return to baseball, despite satisfactory clinical results.

CONCLUSIONS

Costal osteochondral autograft successfully achieved anatomical and biological reconstruction in the treatment of advanced osteochondritis dissecans of the humeral capitellum.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Elbow Injuries in the Adolescent Thrower

PURPOSE OF REVIEW

With an increasing rate of adolescent elbow injuries, especially in throwing athletes, the purpose of this review is to investigate the current literature regarding the diagnosis, treatment, and non-operative and operative outcomes of medial epicondyle fractures, ulnar collateral ligament repair, osteochondritis dissecans of the elbow, and olecranon stress fractures.

RECENT FINDINGS

Acceptable outcomes with both non-operative and operative treatments of medial epicondyle fractures have been reported, with surgical indications continuing to evolve. Unstable osteochondritis dissecans lesions, especially in patients with closed growth plates, require operative fixation, and emerging open and arthroscopic techniques including lesion debridement, marrow stimulation, autograft transfer, and allograft transplantation are described with good outcomes. Ulnar collateral repair has emerged as an exciting treatment option for an avulsion of either end of the ligament in young throwing athletes, with faster rehabilitation times than traditional ulnar collateral ligament reconstruction. Olecranon stress fractures are increasing in prevalence, and when a non-operative treatment course is unsuccessful, athletes have a high return-to-play rate after percutaneous cannulated screw placement. With proper indications, non-operative and operative treatment modalities are reported with a high return-to-play and acceptable clinical outcomes for common elbow injuries, including medial epicondyle fractures, ulnar collateral ligament repair, osteochondritis dissecans of the elbow, and olecranon stress fractures, in adolescent throwing athletes. Further research is needed to better define treatment algorithms, surgical indications, and outcomes.

Editorial Commentary: Robbing Peter to Pay Paul? Is Osteochondral Autograft Transplantation of the Elbow Capitellum Worth the Price?

Osteochondritis dissecans (OCD) of the elbow capitellum is a common disorder that causes pain and functional limitation in the athletic adolescent elbow. Many surgical options have been proposed over the years, but none has stood the test of time. A recent well-written systematic review highlights the treatment options and recognizes a growing trend toward osteochondral allograft transplantation as the ideal solution. Unfortunately, the study also underscores the paucity of evidence on which we base our treatment decisions for OCD of the elbow in the young athlete. Although the potential benefits of osteochondral grafting are encouraging, consideration of associated risks such as donor site morbidity is essential.

Knee donor-site morbidity after mosaicplasty - a systematic review

BACKGROUND

Mosaicplasty has been associated with good short- to long-term results. Nevertheless, the osteochondral harvesting is restricted to the donor-site area available and it may lead to significant donor-site morbidity.

PURPOSE

Provide an overview of donor-site morbidity associated with harvesting of osteochondral plugs from the knee joint in mosaicplasty procedure.

METHODS

Comprehensive search using Pubmed, Cochrane Library, SPORTDiscus and CINAHL databases was carried out through 10th October of 2016. As inclusion criteria, all English-language studies that assessed the knee donor-site morbidity after mosaicplasty were accepted. The outcomes were the description and rate of knee donor-site morbidity, sample's and cartilage defect's characterization and mosaicplasty-related features. Correlation between mosaicplasty features and rate of morbidity was performed. The methodological and reporting quality were assessed according to Coleman's methodology score.

RESULTS

Twenty-one studies were included, comprising a total of 1726 patients, with 1473 and 268 knee and ankle cartilage defects were included. The defect size ranged from 0.85 cm2 to 4.9 cm2 and most commonly 3 or less plugs (averaging 2.9 to 9.4 mm) were used. Donor-site for osteochondral harvesting included margins of the femoral trochlea (condyles), intercondylar notch, patellofemoral joint and upper tibio-fibular joint. Mean donor-site morbidity was 5.9 % and 19.6 % for knee and ankle mosaicplasty procedures, respectively. Concerning knee-to-knee mosaicplasty procedures, the most common donor-site morbidity complaints were patellofemoral disturbances (22 %) and crepitation (31 %), and in knee-to-ankle procedures there was a clear tendency for pain or instability during daily living or sports activities (44 %), followed by patellofemoral disturbances, knee stiffness and persistent pain (13 % each). There was no significant correlation between rate of donor-site morbidity and size of the defect, number and size of the plugs (p > 0.05).

CONCLUSIONS

Osteochondral harvesting in mosaicplasty often results in considerable donor-site morbidity. The donor-site morbidity for knee-to-ankle (16.9 %) was greater than knee-to-knee (5.9 %) mosaicplasty procedures, without any significant correlation between rate of donor-site morbidity and size of the defect, number and size of the plugs. Lack or imcomplete of donor-site morbidity reporting within the mosaicplasty studies is a concern that should be addressed in future studies.

LEVEL OF EVIDENCE

Level IV, systematic review of Level I-IV studies.