IntroductionOsteochondral autograft and allograft transplantation is an

accepted treatment strategy for chondral and osteochondral

defects of the knee and shoulder. The purpose of this study was

to retrospectively review the clinical outcome and graft

morphology in patients with symptomatic osteochondral lesions

treated with osteochondral transplantation.

Hypothesis: The novel center-hole technique for graft impaction

will lead to similar clinical outcomes and will potentially protect

articular cartilage by promoting chondrocyte viability.

MethodsBetween 2006 and 2009 five patients with

symptomatic chondral or osteochondral defects (four

knees, one shoulder) were treated with either

autologous osteochondral transplantation (two) or

osteochondral allograft transplantation (three). The

grafts were press-fit using either standard impaction or

the center-hole technique. Frozen allograft plugs were

used to backfill the autograft donor site in two knees.

Mean age at the time of surgery was thirty-one years.

The mean lesion size was 312 mm2. Clinical

assessment was performed postoperatively using the

International Knee Documentation Committee

(IKDC) score, activity of daily living of the Knee

Outcome Survey (ADL) score, and Short Form-36

(SF-36) at most recent follow-up. Magnetic resonance

imaging was used to evaluate the morphologic and

signal characteristics of the implanted grafts and the

ConclusionsOsteochondral transplantation is an effective treatment

for osteochondral defects in the knee and shoulder. In

our series there was a significant improvement in all

three mean clinical outcome scores. MRI can be a

valuable tool for postoperative evaluation of graft

cartilage and osteointegration. On MRI the center-

hole technique led to increased signal within the bone.

This resolved on subsequent MRI and may not have

any important clinical significance. From a technical

standpoint, this technique allows greater control of the

graft during insertion. Center-hole technique is a

viable alternative to standard impaction resulting in

similar clinical outcome scores, while potentially

improving long term graft survival due to increased

chondrocyte viability at the time of implantation.

Ben B. Bedford, MD, Aruna M. Seneviratne, MD, Stephen J. Nicholas, MD

Nicholas Institute of Sports Medicine and Athletic Trauma (NISMAT), Lenox Hill Hospital, New York

ResultsFive patients met the study criteria with a mean

duration of follow-up of 15.6 months (range, four to

thirty-one months). The mean preoperative IKDC

score was 61.2 ± 17.5 and improved to 77.3 ± 22.3 (p= .016). The mean preoperative ADL score was 73 ± 9.3 and improved to 88.5 ± 10.3 (p=.008). The mean SF-

36 score also improved from 83.4 ± 4.6 to 90.7 ± 5.9

(p=.013). At a mean follow-up of 15.8 months

cartilage sensitive MRI demonstrated a flush plug

appearance in all patients and osseous trabecular

incorporation in 75% of patients. The graft cartilage

had preserved thickness and was isointense to

surrounding cartilage in all patients. With the

exception of increased temporary bone edema in 50%

of patients, the graft properties were similar in those

press-fit with the center-hole technique to those

Clinical Evaluation of a Novel Technique of Impacting Osteochondral Grafts:

Center-Hole Technique vs. Standard Impaction

AcknowledgmentsDr. Michael Vazquez

signal characteristics of the implanted grafts and the

surrounding cartilage. Standard statistical methods

using a paired Student’s t-test were used to analyze the

data.

press-fit with the center-hole technique to those

treated with standard impaction.Threshold for chondrocyteapoptosis

4.5 MPa

MRI T2 Mapping Assess Collagen OrientationOrange = Short T2 values (collagen perpendicular to subchondral plate)

Yellow = Longer T2 values (more random collagen orientation)

Correlates with polarized light microscopy

Standard Center Hole

Center

Hole

Standard

Live/Dead Staining of In-Vitro section of Hyaline Cartilage

Red = Dead Chondrocytes

Green = Live Chondrocytes

Screw is placed in center of graft

Then impacted into recipient site

Screw removed

Distribution of ForceDistribution of Force

Standard Technique Center Hole Technique

Additional Informationwww.nismat.org

www.nyorthodoc.com

www.lenoxhillhospital.org

IntroductionOsteochondral autograft and allograft transplantation is an

accepted treatment strategy for chondral and osteochondral

defects of the knee and shoulder. The purpose of this study was

to retrospectively review the clinical outcome and graft

morphology in patients with symptomatic osteochondral lesions

treated with osteochondral transplantation.

Hypothesis: The novel center-hole technique for graft impaction

will lead to similar clinical outcomes and will potentially protect

articular cartilage by promoting chondrocyte viability.

MethodsBetween 2006 and 2009 five patients with

symptomatic chondral or osteochondral defects (four

knees, one shoulder) were treated with either

autologous osteochondral transplantation (two) or

osteochondral allograft transplantation (three). The

grafts were press-fit using either standard impaction or

the center-hole technique. Frozen allograft plugs were

used to backfill the autograft donor site in two knees.

Mean age at the time of surgery was thirty-one years.

The mean lesion size was 312 mm2. Clinical

assessment was performed postoperatively using the

International Knee Documentation Committee

(IKDC) score, activity of daily living of the Knee

Outcome Survey (ADL) score, and Short Form-36

(SF-36) at most recent follow-up. Magnetic resonance

imaging was used to evaluate the morphologic and

signal characteristics of the implanted grafts and the

ConclusionsOsteochondral transplantation is an effective treatment

for osteochondral defects in the knee and shoulder. In

our series there was a significant improvement in all

three mean clinical outcome scores. MRI can be a

valuable tool for postoperative evaluation of graft

cartilage and osteointegration. On MRI the center-

hole technique led to increased signal within the bone.

This resolved on subsequent MRI and may not have

any important clinical significance. From a technical

standpoint, this technique allows greater control of the

graft during insertion. Center-hole technique is a

viable alternative to standard impaction resulting in

similar clinical outcome scores, while potentially

improving long term graft survival due to increased

chondrocyte viability at the time of implantation.

Ben B. Bedford, MD, Aruna M. Seneviratne, MD, Stephen J. Nicholas, MD

Nicholas Institute of Sports Medicine and Athletic Trauma (NISMAT), Lenox Hill Hospital, New York

ResultsFive patients met the study criteria with a mean

duration of follow-up of 15.6 months (range, four to

thirty-one months). The mean preoperative IKDC

score was 61.2 ± 17.5 and improved to 77.3 ± 22.3 (p= .016). The mean preoperative ADL score was 73 ± 9.3 and improved to 88.5 ± 10.3 (p=.008). The mean SF-

36 score also improved from 83.4 ± 4.6 to 90.7 ± 5.9

(p=.013). At a mean follow-up of 15.8 months

cartilage sensitive MRI demonstrated a flush plug

appearance in all patients and osseous trabecular

incorporation in 75% of patients. The graft cartilage

had preserved thickness and was isointense to

surrounding cartilage in all patients. With the

exception of increased temporary bone edema in 50%

of patients, the graft properties were similar in those

press-fit with the center-hole technique to those

Clinical Evaluation of a Novel Technique of Impacting Osteochondral Grafts:

Center-Hole Technique vs. Standard Impaction

AcknowledgmentsDr. Michael Vazquez

signal characteristics of the implanted grafts and the

surrounding cartilage. Standard statistical methods

using a paired Student’s t-test were used to analyze the

data.

press-fit with the center-hole technique to those

treated with standard impaction.Threshold for chondrocyteapoptosis

4.5 MPa

MRI T2 Mapping Assess Collagen OrientationOrange = Short T2 values (collagen perpendicular to subchondral plate)

Yellow = Longer T2 values (more random collagen orientation)

Correlates with polarized light microscopy

Standard Center Hole

Center

Hole

Standard

Live/Dead Staining of In-Vitro section of Hyaline Cartilage

Red = Dead Chondrocytes

Green = Live Chondrocytes

Screw is placed in center of graft

Then impacted into recipient site

Screw removed

Distribution of ForceDistribution of Force

Standard Technique Center Hole Technique

Additional Informationwww.nismat.org

www.nyorthodoc.com

www.lenoxhillhospital.org

IntroductionOsteochondral autograft and allograft transplantation is an

accepted treatment strategy for chondral and osteochondral

defects of the knee and shoulder. The purpose of this study was

to retrospectively review the clinical outcome and graft

morphology in patients with symptomatic osteochondral lesions

treated with osteochondral transplantation.

Hypothesis: The novel center-hole technique for graft impaction

will lead to similar clinical outcomes and will potentially protect

articular cartilage by promoting chondrocyte viability.

MethodsBetween 2006 and 2009 five patients with

symptomatic chondral or osteochondral defects (four

knees, one shoulder) were treated with either

autologous osteochondral transplantation (two) or

osteochondral allograft transplantation (three). The

grafts were press-fit using either standard impaction or

the center-hole technique. Frozen allograft plugs were

used to backfill the autograft donor site in two knees.

Mean age at the time of surgery was thirty-one years.

The mean lesion size was 312 mm2. Clinical

assessment was performed postoperatively using the

International Knee Documentation Committee

(IKDC) score, activity of daily living of the Knee

Outcome Survey (ADL) score, and Short Form-36

(SF-36) at most recent follow-up. Magnetic resonance

imaging was used to evaluate the morphologic and

signal characteristics of the implanted grafts and the

ConclusionsOsteochondral transplantation is an effective treatment

for osteochondral defects in the knee and shoulder. In

our series there was a significant improvement in all

three mean clinical outcome scores. MRI can be a

valuable tool for postoperative evaluation of graft

cartilage and osteointegration. On MRI the center-

hole technique led to increased signal within the bone.

This resolved on subsequent MRI and may not have

any important clinical significance. From a technical

standpoint, this technique allows greater control of the

graft during insertion. Center-hole technique is a

viable alternative to standard impaction resulting in

similar clinical outcome scores, while potentially

improving long term graft survival due to increased

chondrocyte viability at the time of implantation.

Ben B. Bedford, MD, Aruna M. Seneviratne, MD, Stephen J. Nicholas, MD

Nicholas Institute of Sports Medicine and Athletic Trauma (NISMAT), Lenox Hill Hospital, New York

ResultsFive patients met the study criteria with a mean

duration of follow-up of 15.6 months (range, four to

thirty-one months). The mean preoperative IKDC

score was 61.2 ± 17.5 and improved to 77.3 ± 22.3 (p= .016). The mean preoperative ADL score was 73 ± 9.3 and improved to 88.5 ± 10.3 (p=.008). The mean SF-

36 score also improved from 83.4 ± 4.6 to 90.7 ± 5.9

(p=.013). At a mean follow-up of 15.8 months

cartilage sensitive MRI demonstrated a flush plug

appearance in all patients and osseous trabecular

incorporation in 75% of patients. The graft cartilage

had preserved thickness and was isointense to

surrounding cartilage in all patients. With the

exception of increased temporary bone edema in 50%

of patients, the graft properties were similar in those

press-fit with the center-hole technique to those

Clinical Evaluation of a Novel Technique of Impacting Osteochondral Grafts:

Center-Hole Technique vs. Standard Impaction

AcknowledgmentsDr. Michael Vazquez

signal characteristics of the implanted grafts and the

surrounding cartilage. Standard statistical methods

using a paired Student’s t-test were used to analyze the

data.

press-fit with the center-hole technique to those

treated with standard impaction.Threshold for chondrocyteapoptosis

4.5 MPa

MRI T2 Mapping Assess Collagen OrientationOrange = Short T2 values (collagen perpendicular to subchondral plate)

Yellow = Longer T2 values (more random collagen orientation)

Correlates with polarized light microscopy

Standard Center Hole

Center

Hole

Standard

Live/Dead Staining of In-Vitro section of Hyaline Cartilage

Red = Dead Chondrocytes

Green = Live Chondrocytes

Screw is placed in center of graft

Then impacted into recipient site

Screw removed

Distribution of ForceDistribution of Force

Standard Technique Center Hole Technique

Additional Informationwww.nismat.org

www.nyorthodoc.com

www.lenoxhillhospital.org