Session III - Hip & Geriatrics

Fri., 10/9/09 Hip & Geriatric, Paper #46, 11:17 am OTA-2009

Outcomes of Length Stable Fixation of Femoral Neck Fractures

Sreevathsa Boraiah, MD1 (7-Wright Medical); Omesh Paul, MD2 (n);
Michael J. Gardner, MD3 (5A-Synthes, Expanding Orthopedics; 7-AO, Synthes, Smith &Nephew);
Joseph U. Barker, MD2 (n); Robert J. Parker, BS2 (n); David Helfet, MD2 (7, 8-Synthes);
Dean Lorich, MD2 (n);
1Westchester Medical Center, Valhalla, New York, USA;
2Hospital for Special Surgery, New York, New York, USA;
3Washington University School of Medicine, Saint Louis, Missouri, USA

Purpose: The most common implants for treating unstable femoral neck fractures are sliding constructs, which allow postoperative collapse. Successful healing typically is a malunion with a shortened femoral neck. Functional sequelae resulting from altered femoral neck biomechanics has been increasingly reported. Reoperation rate due to nonunion, avascular necrosis, hardware cutout, and prominence is high with this treatment modality. We evaluated the outcomes of patients with femoral neck fractures treated with stable calcar pivot reduction, intraoperative compression across the fracture, and stabilization with length-stable implants.

Methods: 54 patients with femoral neck fractures underwent open reduction and internal fixation. Average follow-up duration was 23.6 months (range, 15-36 months). There were 23 Garden I, 2 Garden II, 14 Garden III, and 15 Garden IV fractures. Reduction was achieved through a modified Smith-Petersen approach. Fractures were compressed initially, and subsequently stabilized with a length-stable device. Postoperative radiographs were assessed for change in fracture alignment. Variation in the femoral neck offset and abductor lever arm measurements was performed using the contralateral hip as control. Functional outcome was assessed using Short Form-36 (SF-36), Harris hip score (HHS), and a gait analysis device.

Results: The mean patient age was 78 years. 51 patients (94%) healed without complications. Surgical fixation failed in 2 patients and 1 patient developed avascular necrosis. The average femoral neck shortening was 1.7 mm. The average difference in femoral neck offset and the abductor lever arm measurement at the latest follow-up was 3.5 mm and 1.5 mm, respectively. The average score on physical, mental components of SF-36 and HHS was 42, 47, and 87, respectively. By 6 months, patients on average recovered 94% of the single-limb stance time, 98% of cadence, 90% of cycle duration, and 96% in stride length compared to the uninjured side.

Conclusions: Reduction with a stable calcar pivot, intraoperative compression, and length-stable fixation can achieve high union rates with minimal femoral neck shortening and improved functional outcomes.

Disclosure: (n=Respondent answered 'No' to all items indicating no conflicts; 1=Board member/owner/officer/committee appointments; 2=Medical/Orthopaedic Publications; 3=Royalties; 4=Speakers bureau/paid presentations; 5A=Paid consultant or employee; 5B=Unpaid consultant; 6=Research or institutional support from a publisher; 7=Research or institutional support from a company or supplier; 8=Stock or Stock Options; 9=Other financial/material support from a publisher; 10=Other financial/material support from a company or supplier).

• The FDA has not cleared this drug and/or medical device for the use described in this presentation   (i.e., the drug or medical device is being discussed for an “off label” use).  ◆FDA information not available at time of printing. Δ OTA Grant