1. Reconstruction of Focal Femoral Head Cartilage Defects With a Chitin-Based Scaffold 
Ahmed Al-Qarni, M.B.B.S., S.B.(Orth), Matthew R. Lewington, M.D., F.R.C.S.C., Ivan H. Wong, M.D., M.Sc., F.R.C.S.C., Dip. Sports Medicine 
Arthroscopy Techniques 
Volume 5, Issue 2, Pages e257-e262 (April 2016)
DOI: /j.eats
Copyright © 2016 Arthroscopy Association of North America Terms and Conditions

2. Fig 1
The patient is in the supine position on a traction table. The operative site has been draped. The greater trochanter has been outlined in marker. The anterior superior iliac spine (ASIS; X) and portal sites are marked (A-D). (A) The midanterior portal is localized roughly 2 cm distal to the anterolateral portal, halfway between a line drawn from the anterior superior iliac spine through the proximal pole of the patella and the midaxillary line. (B) The anterolateral portal is located just anterior to the tip of the greater trochanter. (C) The posterolateral portal is located just posterior to the tip of the greater trochanter (the spinal needle is in this portal). (D) The location of the spinal needle, introduced percutaneously, is shown; it is directed to enter the joint posterior to the posterolateral portal. This is used to drain the joint before BST-CarGel application.
Arthroscopy Techniques 2016 5, e257-e262DOI: ( /j.eats )
Copyright © 2016 Arthroscopy Association of North America Terms and Conditions

3. Fig 2
Procedures performed before microfracture and BST-CarGel application. The patient is in the supine position on the traction table. (A) With the arthroscope in the anterolateral portal, a burr (b; Smith & Nephew) is used to perform an acetabular osteoplasty on the acetabulum (acet). The frayed labrum (Lab) can be seen below the burr. The femoral head (FH) is distracted through the use of the traction table. (B) With the arthroscope in the anterolateral portal, the labral repair has been completed. Sutures (S) are visible attached to anchors (Smith & Nephew) inserted in the acetabulum, with a good seal on the FH when the hip is reduced. (C) With the arthroscope in the anterolateral portal, femoral osteoplasty is performed with a curette (c; Smith & Nephew) to remove cartilage and soft tissue at the FH–neck (FN) junction. The burr is then used to remove the underlying bone to ensure that the cam lesion is completely resected.
Arthroscopy Techniques 2016 5, e257-e262DOI: ( /j.eats )
Copyright © 2016 Arthroscopy Association of North America Terms and Conditions

4. Fig 3
Preparation and microfracture of femoral head defect. The patient is in the supine position on the traction table. (A) Femoral defect (L) as viewed through the anterolateral portal. This is located at the posterior-superior part of the femoral head (FH). (B) A curette (c; Smith & Nephew) is used to debride the lesion to a stable cartilaginous rim. (C) A 5-mm probe (P; Smith & Nephew) is inserted to measure the size of the defect. (D) A microfracture pick (MF; Smith & Nephew) is used to perform a microfracture procedure on the lesion (L); this is driven through the subchondral bone until marrow and blood extrude. (E) The hip is drained of fluid. The spinal needle (circle) is shown in the inferior aspect. This is inserted percutaneously in the posterior aspect of the hip distal to the trochanter. It is aimed to enter the hip joint posterior to the posterolateral portal. Once in the joint, the spinal needle is attached to suction to drain the joint. (F) Neuro-patties (NP) are inserted using a grasper through a metal hip cannula (Smith & Nephew) to dry the microfractured area once the hip is dry.
Arthroscopy Techniques 2016 5, e257-e262DOI: ( /j.eats )
Copyright © 2016 Arthroscopy Association of North America Terms and Conditions

5. Fig 4
Insertion of BST-CarGel, viewed through anterolateral portal. The patient is in the supine position on the traction table. The product has been mixed with the patient's blood and kept at body temperature before insertion. (A) A spinal needle (circle) is inserted into the dry hip through the posterolateral portal. This needle is directed into the previously microfractured defect (L) in the femoral head (FH). (B) The BST-CarGel mixture (c) is instilled drop-wise into the defect by the spinal needle (circle). (C) At the end of the procedure, the 3-dimensional contour of the FH has been reconstituted by the product (c) and the needle (circle) is withdrawn.
Arthroscopy Techniques 2016 5, e257-e262DOI: ( /j.eats )
Copyright © 2016 Arthroscopy Association of North America Terms and Conditions