Rectus Femoris Heterotopic Ossification: Combined Arthroscopic and Open Resection With Allograft Reconstruction and Concomitant Treatment of Femoroacetabular Impingement.

Background: Heterotopic ossification (HO), or the abnormal formation of bone in extra-skeletal tissue, is a well-known complication of orthopedic trauma, tendon avulsions, chronic injuries, spinal cord injuries, and soft tissue damage from surgery. Heterotopic ossification commonly develops at the direct or indirect head of the rectus femoris. Athletes are especially susceptible to chronic microtearing and acute tendon avulsion, which may result in HO. When HO develops in the setting of concurrent intra-articular hip pathology, it may be amendable to arthroscopic excision, depending on its size and location. Indications: Heterotopic ossification that develops adjacent to the hip joint can affect range of motion of the joint and is often a source of pain. Arthroscopic excision is indicated when the HO that develops within or about the hip joint is symptomatic and is of a location and size that it can be reached and excised arthroscopically. Technique Description: In this technical note, we describe our method to excise HO using initial arthroscopic surgery to address femoroacetabular impingement syndrome (FAIS) and perform initial dissection of the HO fragment. Heterotopic ossification resection was then completed via an anterior open approach followed by reconstruction of the rectus femoris origin with Achilles allograft. This is followed by our HO prophylaxis protocol of indomethacin 75 mg daily for 4 days, followed by naproxen 500 mg 2 times daily through postoperative day 30, although many other regimens exist for HO prophylaxis. Results: Using arthroscopy for the removal of symptomatic HO at the time of surgery allows for the management of concomitant intra-articular pathology and efficient and precise dissection of the undersurface of the HO fragment. Discussion/Conclusion: Heterotopic ossification is a well-characterized complication of soft tissue damage, including tendon avulsion, trauma, previous surgery, and chronic microtear of the hip musculature. Oftentimes, HO develops in a location that can be reached arthroscopically. Surgeons should consider combining intra-articular arthroscopic surgery with arthroscopic excision of HO when appropriate, noting that there are many advantages to arthroscopic removal when compared with open procedures. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.