Minimally invasive subcutaneous anterior fixation of pelvic fractures in the elderly: case report and literature review

Abstract

BACKGROUND: As our population ages, the incidence of pelvic fragility fractures will rise accordingly. Despite these fractures having similar mortality rates to proximal femur fractures, there exist discrepancies between the management of these injuries. Although a number of pelvic fragility fractures can be treated successfully with conservative means, early treatment with appropriate surgical means should be considered in those failing conservative treatment or with unstable fracture patterns. CASE REPORT: We present an 84-year-old female who sustained a pelvic fragility fracture after a low-energy fall. Despite adequate conservative treatment, she was unable to mobilise. She was taken for anterior and posterior fixation, using our modified minimally invasive subcutaneous technique (the Bridging Infix) for anterior fixation. At the six-week follow-up she had regained full independent mobility. She had three syncope-related falls during this period, but radiographs revealed no sign of implant displacement. One year after her surgery she had complete union of her fracture, good function and no desire to have the implant removed. DISCUSSION: With the expected increase in pelvic fragility fractures due to the growing elderly population, our understanding of these injuries has begun to change. Occult posterior ring injuries have been described in up to 80% of cases, while fracture progression to unstable patterns can occur in up to 15% of stable patterns. Despite conservative management being the primary treatment of choice, these patients suffer morbidity and mortality rates comparable to proximal femur fractures. Early appropriate surgical management should be considered in patients failing to mobilise. Various surgical techniques have been described, each with their own advantages and disadvantages. Newer minimally invasive techniques are gaining favour, especially for use in elderly patients. These constructs combine the low profile benefits of internal plate fixation with ex-fix principles. CONCLUSION: The Bridging Infix is a modified technique for minimally invasive subcutaneous anterior pelvic fixation. Its use can strongly be considered by even the general orthopaedic surgeon in cases where patients are too frail for extensive or invasive surgeries, such as open reduction and internal fixation with plate and screws. Level of evidence: Level 5 Keywords: pelvic fracture, anterior pelvic fixation, elderly, minimally invasive

The Bridging Infix: a modified, minimally invasive subcutaneous anterior pelvic fixation technique

“…2,5 This 'Bridging Infix' technique described above, and used by Strydom and Snyckers, is a modification of both the abovementioned techniques and we propose that it can be used as an alternative anterior fixation method in an attempt to address the potential complications and drawbacks described. 9 It follows the same anatomical course as the Pelvic Bridge, hence should have a similar incidence of LFCN neuropraxia. The lack of medial fixation negates the risk of bladder injury with screw placement and allows for its application in patients with Nakatani zone I fractures.…”

“…Successful use of the Bridging Infix technique was first described by Strydom and Snyckers. 9 The aim is to limit complications associated with external fixator use, while retaining the advantages of using internal implants, but using the same external fixation principles. 2,3,10 Our technique also aims to reduce the described complications of other minimally invasive subcutaneous fixation methods, such as lateral cutaneous femoral nerve (LCFN) neuropraxia, heterotopic ossification and patient discomfort.…”

Establishing the safety of the lateral femoral cutaneous nerve when using the Bridging Infix for anterior pelvic fixation

“…The current study demonstrated that the use of the Bridging Infix for anterior pelvic fixation did not pose a significant risk to the LFCN. The LFCN is currently the most prevalent structure mentioned in literature relating to anterior pelvic fixation, 2,5,21,22,[24][25][26] and numerous studies have looked at its relationship to the ASIS. 10,16,18,19,[27][28][29][30][31][32][33][34] Additional and more pertinent distances were needed in order to establish the safety of the Bridging Infix technique, as structures in close relation to the ASIS, iliac crest and pubic tubercle would potentially be at risk during dissection and implant placement.…”

“…Due to the rigidity of the formalin-fixed cadavers, it was deemed unfeasible to easily create a subcutaneous tunnel as required. Therefore, the implantation procedure was a modified version published by Strydom et al 21 In the fresh frozen samples, the surgical technique was strictly adhered to as the tissue elasticity was identical to a live patient undergoing the surgical procedure.…”

“…[17][18][19][20] Strydom et al proposed a modified technique using an internal bridge plate and rod technique. 21 This technique combines the benefits of open reduction internal fixation (ORIF) with external fixation methods, with the aim of reducing known complications. It is a modification of both the pelvic bridge and INFIX described by Hiesterman et al 22 and Vaidya et al, 23 respectively.…”