Achieving a Perfectly Spherical Femoroplasty: Pearls, Pitfalls, and Optimal Surgical Technique

Figures

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  Fig 1. (A) Right hip in a patient in the modified supine position with the hip in neutral flexion, the head toward the left and feet to the right during intraarticular joint access. The AL, MA, and DALA portals are shown. The 70° arthroscope (blue arrow) is placed in the AL portal, working instrument (green arrow) in the MA portal and a traction suture (black arrow) in the DALA portal. (B) An arthroscopic view of the right femoral head/neck junction and capsule (black arrow) Because T-capsulotomies are not routinely done, a traction suture is placed within the inferior capsule leaflet. As an assistant adds traction on a clamped suture, greater intracapsular exposure is achieved and visualization of the joint is improved, revealing the cam deformity (blue arrow). Note: this is a crucial step, as it allows for improved visualization to fully assess the peripheral compartment. (AL, anterolateral; DALA, distal anterolateral accessory; MA, mid-anterior.)

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  Fig 2. Postoperative fluoroscopic views of the right hip taken at the 6 corresponding patient operative extremity and C-arm positions (Table 3), producing the 6 anatomical regions of the head/neck junction. (A) Anterolateral zone (12:30-1:30). (B) Anteromedial zone A (1:30-2:30). (C) Anteromedial zone B (2:30-3:30). (D) Lateral zone (11:30-12:30). (E) Posterolateral zone (10:30-11:30). (F) Further posterolateral/ posterosuperior (+limb traction) zone (9:30-10:30).

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  Fig 3. Position 1. Patient operative extremity and corresponding C-arm positioning needed to isolate the anterolateral zone (12:30-1:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. (A) operative hip is in 45° flexion; (B) C-arm is set to 0°, −30° cantilever. (ca, cantilever; fl, flexion.)

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  Fig 4. Starting fluoroscopic Dunn view image of the anterolateral femoral head/neck junction of the right hip. Proximal extent of the cam lesion (highlighted) is identified.

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  Fig 5. View from the anterolateral portal of the right hip with a 70° arthroscope. Note the removal of the periosteum from the surface of the femoral head. (A, ablated area; Dx, distal; P, periosteum; Px, proximal.)

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  Fig 6. View from the anterolateral portal of the right hip with a 70° arthroscope. Note marked resection level starting distal along anterolateral femoral head/neck junction, to improve offset ratio as well as resect cam lesion. (Bu, burr; F, femoral head; Dx, distal; plC, posterolateral capsule; Px, proximal.)

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  Fig 7. Dunn view of the anterolateral zone (12:30-1:30) of the femoral head/neck region (position 1) of the right hip showing gradual resection of the cam lesion distally to proximally. The femoral head/neck junction has been recontoured with the cam lesion fully resected. Note: Extreme care was taken to avoid over-resection of the head/neck junction by maintaining convexity.

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  Fig 8. Position 2. Patient operative extremity and corresponding C-arm positioning needed to isolate the snteromedial zone A (1:30-2:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. (A-B) Operative hip is in 60° flexion, 30° external rotation, 25° adduction. The C-arm remains at 0° tilt, −30° cantilever. cantilever. Again, C-arm tilt is added to correct for Trendelenburg. (er, external rotation; fl, flexion.)

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  Fig 9. Position 3. Patient operative extremity and corresponding C-arm positioning needed to isolate the snteromedial zone B (2:30-3:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. Operative hip is in 60° flexion, 60° external rotation, 25° adduction. The C-arm remains at 0° tilt, −30° cantilever. cantilever. Again, C-arm tilt is added to correct for Trendelenburg. (ca, cantilever; er, external rotation.)

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  Fig 10. Position 4. Patient operative extremity and corresponding C-arm positioning needed to isolate the lateral zone (11:30-12:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. (A) Operative hip is in 0o flexion, 0o rotation (neutral position); (B) The C-arm is set to 0° tilt, −10° cantilever. Note: the patient is intentionally placed in Trendelenburg to minimize perineal pressure.17 Sometimes, C-arm tilt is added to correct for this (dotted lines). (ca, cantilever.)

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  Fig 11. Position 5. Patient operative extremity and corresponding C-arm positioning needed to isolate the posterolateral zone (10:30-11:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. Operative hip remains in 0° flexion and 0° rotation (neutral position). The C-arm is set to 0° tilt, 0° cantilever. (ca, cantilever.)

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  Fig 12. Position 6. Patient operative extremity and corresponding C-arm positioning needed to isolate further posterolaterally/posterosuperior zone (9:30-10:30) of the head/neck region during the 6-pronged approach femoroplasty. The patient is in a modified supine position with the head toward the left and feet to the right. The angle of the C-arm is shown in reference to the mayo stand as horizontal. Operative hip is in 0° flexion, 30° internal rotation to target the head/neck region further posterolaterally. Traction is added to target the posterosuperior region. The C-arm remains at 0° tilt, 0° cantilever. (ca, cantilever; ir, internal rotation.)