Static Helical Screw Locking of Pertrochanteric Femur Fractures Using the TFN-A

Official title

Static Helical Screw Locking of Pertrochanteric Femur Fractures Using the TFN-Advanced Proximal Femoral Nailing System - a Randomized Trial

Overview

The study will investigate the shortening and collapse of pertrochanteric fractures following surgical management with the TFN-Advanced nailing system. The focus will be on comparing radiographic assessments of nails which have been statically locked versus dynamically locked. This is a randomized control study with the initial invention being randomized to either statically locking or dynamically locking. For a two-month period, all eligible patients will receive the randomized allocated treatment, then treatment will switch to the alternate treatment for the next two months and will continue to alternate treatments for two-month periods until study enrollment has completed.

Detailed description

Hip fractures are common injuries in the elderly population that result in significant morbidity and mortality and a significant burden on health care systems. Hip fractures can be treated with arthroplasty or with internal fixation, depending on the fracture pattern. Cephalomedullary nailing (CMN) has become one of the established treatments for intertrochanteric hip fractures with a wide variety of implant designs from many different companies. The TFN-ADVANCED™ Proximal femoral nailing system (TFN-A) is a novel implant for treating intertrochanteric and subtrochanteric proximal femur fractures with a paucity of published literature on the performance of this implant.

A method to decrease the amount of fracture compression is to use the set screw to lock the screw "statically" so it does not slide to the same degree as if the screw is placed in the "dynamic" or sliding position. To the knowledge of the investigators, the role of statically locking the screw to prevent fracture collapse has not been studied. Statically locking CMN to treat hip fractures has become standard of care at the Royal Columbian Hospital with all the investigating surgeons having adopted this practice in an attempt to prevent significant fracture collapse and neck shortening. Anecdotally, the investigators have not seen significant rates of cephalic screw cut-out over the past five years, and believe the investigators' screw cut-out rates are lower than what is reported in the literature. The investigators have been using the Gamma Nail (Stryker) to statically lock the screw as the previous TFN lacked the ability for static locking. However, with the advent of the TFN-A, the investigators have adopted this implant as their long cephalomedullary nail of choice for fixation of pertrochanteric femur fractures.

Interventions

• Procedure Dynamic Rotational Locking
  Performed, as per the Synthes technique guide, using the 5mm hex flexible set screwdriver and then loosening the set screw by one-half turn of the screwdriver.
• Procedure Static Locking
  Performed by using the torque-limiting set screwdriver and locking the set screw down onto the helical screw to prevent dynamic sliding of the screw within the nail.

Primary outcome measures

• Radiographic Assessment [Time frame: 12 months post treatment]

Secondary outcome measures (4)

• Fracture Reduction Quality [Time frame: Intra-operatively]
• Femoral Offset [Time frame: 1 day post-op, 6 weeks, 12 weeks, 6 months, and 12 months]
• Tip-Apex distance [Time frame: 1 day post-op, 6 weeks, 12 weeks, 6 months, and 12 months]
• Complications [Time frame: intra-operatively, 1 day post-op, 6 weeks, 12 weeks, 6 months, and 12 months]

Eligibility criteria

Inclusion criteria

• Patients >18 years of age
• AO/OTA 31-A fractures who the surgeon deems eligible for treatment with a cephalomedullary nail
• Open and closed fractures
• Ambulatory prior to injury (with or without walking aides)
• Native (non-fractured, no implant) contralateral hip
• Willing and able to sign consent (substitute decision maker)

Exclusion criteria

• Contralateral hip fracture or hip arthroplasty
• Fracture not amenable to treatment with a cephalomedullary nail
• Non-ambulatory patient
• Fractures >14 days (time of injury to OR)
• Bilateral pertrochanteric hip fractures
• Non-unions
• Pathologic fractures
• Periprosthetic fractures
• Patients with spinal injury
• Incarceration
• Pregnancy
• Limited life expectancy due to significant medical co-morbidities or medical contra-indications to surgery
• Likely problems, in the judgement of the investigators, with maintaining follow-up (i.e., patients with no fixed address, report a plan to move out of town, or intellectually challenged patients without adequate family support).

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

Canada · 1 center

• Royal Columbian Hospital/Fraser Health Authority — New Westminster

Publications

• Kanis JA, Oden A, McCloskey EV, Johansson H, Wahl DA, Cooper C; IOF Working Group on Epidemiology and Quality of Life. A systematic review of hip fracture incidence and probability of fracture worldwide. Osteoporos Int. 2012 Sep;23(9):2239-56. doi: 10.1007/s00198-012-1964-3. Epub 2012 Mar 15. PMID 22419370
• Zickel RE. A new fixation device for subtrochanteric fractures of the femur: a preliminary report. Clin Orthop Relat Res. 1967 Sep-Oct;54:115-23. No abstract available. PMID 5589594
• Stapert JW, Geesing CL, Jacobs PB, de Wit RJ, Vierhout PA. First experience and complications with the long Gamma nail. J Trauma. 1993 Mar;34(3):394-400. doi: 10.1097/00005373-199303000-00015. PMID 8483181
• Lecerf G, Fessy MH, Philippot R, Massin P, Giraud F, Flecher X, Girard J, Mertl P, Marchetti E, Stindel E. Femoral offset: anatomical concept, definition, assessment, implications for preoperative templating and hip arthroplasty. Orthop Traumatol Surg Res. 2009 May;95(3):210-9. doi: 10.1016/j.otsr.2009.03.010. Epub 2009 May 6. PMID 19423418
• Paul O, Barker JU, Lane JM, Helfet DL, Lorich DG. Functional and radiographic outcomes of intertrochanteric hip fractures treated with calcar reduction, compression, and trochanteric entry nailing. J Orthop Trauma. 2012 Mar;26(3):148-54. doi: 10.1097/BOT.0b013e31821e3f8c. PMID 21918483
• Yoo JH, Kim TY, Chang JD, Kwak YH, Kwon YS. Factors influencing functional outcomes in united intertrochanteric hip fractures: a negative effect of lag screw sliding. Orthopedics. 2014 Dec;37(12):e1101-7. doi: 10.3928/01477447-20141124-58. PMID 25437085
• Gausden EB, Sin D, Levack AE, Wessel LE, Moloney G, Lane JM, Lorich DG. Gait Analysis After Intertrochanteric Hip Fracture: Does Shortening Result in Gait Impairment? J Orthop Trauma. 2018 Nov;32(11):554-558. doi: 10.1097/BOT.0000000000001283. PMID 30239477
• Bishop JA, Palanca AA, Bellino MJ, Lowenberg DW. Assessment of compromised fracture healing. J Am Acad Orthop Surg. 2012 May;20(5):273-82. doi: 10.5435/JAAOS-20-05-273. PMID 22553099

Identifiers

NCT: NCT04851509 · FHREB#: 2021-015

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗