A woman with right hip pain

Issue: January 2017

ByGregory J. Galano, MD

ByDavid A. Porter, MD

A 29-year old active woman was presented to the office with a long-standing history of right hip pain. She previously had staged, bilateral, arthroscopic hip surgery, including femoral osteoplasties for cam lesions and resultant labral repair, which yielded satisfactory initial results. She later presented persistent right hip pain keeping her awake at night.

On physical examination, there was no tenderness to palpation and her right hip range of motion was 50° of extension to 100° of flexion, 20° of adduction, 45° of abduction and 30° of internal rotation. There was notable pain with internal and external rotation of the hip. She had no signs of impingement or instability during this time. She mainly complained about a vague deep groin pain. Anteroposterior and frog-leg lateral radiographs (Figure 1) were performed in addition to a subsequent MRI of the hip (Figure 2) as part of her initial evaluation.

Preoperative AP pelvis and lateral hip radiographs — Preoperative AP pelvis (a) and lateral hip (b) radiographs demonstrate postoperative changes to bilateral hips and bilateral femoral osteochondroplasty for FAI.

Preoperative MRI arthrogram (coronal and sagittal T2-weighted images) demonstrate a new high-grade partial-thickness cartilage defect over the superomedial femoral head measuring 5-mm transverse x 8-mm AP. There is associated faint subchondral marrow edema in this location with slight less than 1-mm indentation of the subchondral.

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Osteochondral lesion in the superior aspect of the femoral head

The patient’s lesion was diagnosed on MRI, but not appreciated on plain radiographs. The lesion measured approximately 5 mm x 8 mm. While postsurgical osteonecrosis (ON) could be possible, the patient’s MRI was consistent with an osteochondral lesion rather than collapse and edema of the femoral head. The decision to perform an osteochondral autograft transfer (OAT) from the ipsilateral knee was made due to the patient’s age, activity level, location, size and osseous involvement of the lesion. Other surgical options discussed included microfracture or autologous chondrocyte implantation (ACI). However, researchers believed the OAT procedure would lead to the most successful outcome based on the literature.

The patient was positioned in the left lateral decubitus position on the operating table and a surgical dislocation of the hip was performed with a trochanteric osteotomy. A posterior Kocher approach to the hip was performed and after splitting the deep fascia, a transverse osteotomy was made with a sagittal saw just above the level of the short external rotators. Care was taken to establish a 3-cm to 4-cm trochanteric fragment, which later would be repaired.

Postoperative AP pelvis radiograph status post-internal fixation of trochanteric flip osteotomy with screws is shown.

The hip was dislocated anteriorly to preserve the blood supply from the medial femoral circumflex artery. Both the acetabular cartilage and labrum were intact. However, the osteochondral femoral lesion superior to the fovea was identified and measured to be less than 1 cm. A superolateral incision over the ipsilateral knee was made, and the lateral femoral condyle was exposed. A 1-cm osteochondral plug was harvested from the superolateral corner of the trochlea, and the plug was placed in saline on the back table. StimuBlast demineralized bone matrix putty (Arthrex) was placed flush into the trochlear donor site. Attention was turned to the femoral head, which was again dislocated and visualized. The lesion was excised using a recipient harvester. The osteochondral donor plug was placed into the femoral head defect and impacted into place. The hip was reduced and intraoperative examination demonstrated good range of motion and stability. The trochanteric osteotomy was reduced and internally fixed with three 4-mm cortical screws.

Postoperative coronal and sagittal MRI — Postoperative coronal (a) and sagittal (b) MRI 4 months status post-osteochondral allograft transfer procedure in the location of the previously identified osteochondral lesion. The allograft appears well incorporated into the femoral head. There is mild marrow edema surrounding the allograft, which is likely post-surgical healing of osteochondral autograft.

Postoperatively, the patient was maintained in a hip abduction brace and remained non-weight-bearing with crutches on the affected extremity and began physical therapy immediately. There were no restrictions with regard to range of motion. Six weeks postoperatively, the patient beared weight as tolerated. Radiographs (Figure 3) and a MRI (Figure 4) were performed at 16 weeks postoperatively, which demonstrated osteointegration of the osteochondral graft.

Discussion

Treatment of a hip joint chondral lesion is challenging due to the complex anatomy and difficult accessibility. The increased risk of symptomatic progression of osteoarthritis (OA) has demanded treatment strategies similar to those used for osteochondral lesions of the knee, talus and capitellum. These treatment modalities range from arthroscopic debridement and microfracture to ACI and osteochondral autograft or allograft transplantation. While there is a paucity of literature regarding femoral head autologous osteochondral graft transplantation, the success of this procedure in treating full-thickness osteochondral lesions of the knee has been extrapolated for its use in the hip joint. This procedure has been described in the femoral head. However, long-term outcome and indications are still unclear.

Full-thickness osteochondral lesions can be devastating in weight-bearing joints, as patients often report constant pain and catching of the femoral head with daily movements. While full-thickness lesions often have the potential to heal through mesenchymal cells producing a type 1 fibrocartilage matrix, this has been shown to be biomechanically inferior to otherwise normal hyaline cartilage of the articular surface. Microfracture is a treatment option that allows fibrocartilage healing of the lesion and is often used for small lesions or in cases where the lesion was not previously identified. Indications for microfracture are limited to minimal OA (Tonnis Grade 0 to 1) and lesion size smaller than 4 cm. Mosaicplasty allows for the incorporation of hyaline-based osteochondral autograft into the femoral head, providing a more stable and biologically similar matrix. Initially described by László Hangody, MD, PhD, and Péter Füles, MD, this technique has fallen into favor due to its long-term clinical success.

Osteochondral autograft transplants have been described for the treatment of large osteochondral lesions of the knee secondary to trauma or spontaneous ON. However, there is limited literature for its use in the hip joint. For the knee literature at 10-year follow-up, the data has demonstrated a significantly higher success rate for mosaic osteochondral autograft transplants in the knee joint when compared to microfracture. Other long-term follow-up of more than 1,000 patients with mosaicplasty have demonstrated good to excellent results in greater than 90% of patients with femoral condylar and talar implantations. As a result of these outcomes, management of analogous osteochondral lesions in the hip has been treated by a similar approach. Few reports describe the use of this technique for femoral head fractures. Other reports describe its use in femoral head ON.

Hangody and his colleagues reported on the largest series of osteochondral autograft transplants in hip patients. The difficulty in managing these femoral head lesions with autologous graft transplantation is it requires access to the hip joint through a surgical dislocation of the hip with a trochanteric flip osteotomy, which is technically demanding and has its own inherent complications.

Options for the patient discussed herein include microfracture, mosaicplasty, ACI and osteochondral allograft. ACI is also another option with good reported results in the knee. However, it requires the need for two surgeries. Osteochondral autograft requires a surgical dislocation, but provides a repair with hyaline cartilage and allows for earlier weight-bearing. Galano’s protocol for this patient was touch-toe weight-bearing for 6 weeks followed by advancement to full weight-bearing.

In conclusion, preservation of the hip joint in the young active patient with a chondral injury is essential. All of the aforementioned options have reported success despite limited long-term data and should be considered when managing chondral lesions of the hip. It is important to identify demographic factors in patients in order to provide them the most appropriate treatment. For this patient, while one can make the argument for microfracture, there is currently not enough data in the hip literature to identify the most appropriate option.

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For more information:
David A. Porter, can be reached at 6350 E. 106th St., Fishers, IN 46038; email: dporter224@gmail.com.
Gregory J. Galano, MD, can be reached at Lenox Hill Hospital, 210 E 64th St., 4th Floor, New York, NY 10065; email: galano7@gmail.com.

Disclosures: Porter and Galano report no relevant financial disclosures.