Commentary & Perspective on
"In Situ Fixation of Pelvic Nonunions Following Pathologic and Insufficiency Fractures"
By Dana C. Mears, MD, PhD, and John H. Velyvis, MD

Commentary & Perspective by
David L. Helfet, MD*, and Jeffrey Richmond, MD*,
Orthopaedic Trauma Service, Hospital for Special Surgery, New York, NY

This retrospective study of the treatment of pelvic nonunions following pathologic and insufficiency fractures represents the authors' substantial experience with an uncommon and difficult problem. Pelvic fractures are difficult to treat under the best of circumstances; nonunion is not uncommon and is potentially disabling¹. Treatment of nonunions after pathologic fracture is a major surgical challenge, as evidenced by the data presented here, and the problems are further compounded because the majority of patients with pathological bone are elderly. With the average age of the population in the United States rapidly increasing, treatment of these fractures may become a more compelling issue.

The majority of low-energy pelvic fractures in the elderly are the "isolated" pubic rami fractures. With the usual mechanism of injury, these should also be associated with a posterior injury as well, although these lesions are often undetected on plain radiographs. Anecdotal experience suggests that the vast majority of these injuries heal. Although most of these patients fully recover, in one series 95% (sixty of sixty-three patients) required an average of two weeks of hospitalization for pain control and progressive mobilization². Given this morbidity for simple pelvic fractures in an osteopenic (pathologic) population, one can anticipate that nonunion will result in even greater costs and disability in the future.

Mears and Velyvis reported the results of in situ fixation of symptomatic pelvic fracture nonunions with a variety of diagnoses and fracture characteristics in forty-four patients. Similarly, a variety of surgical strategies were employed. Eighty-two percent united after in situ fixation alone, and 88% united after additional surgery. This is remarkable given the poor pelvic "bone stock" that is available for fixation of these long-standing pathologic and insufficiency fractures. Despite the success of surgery, only 55% of the forty-four patients were "highly satisfied"; 27% were "satisfied" and 18% were "unsatisfied" with the surgical result. A subgroup of patients complained of persistent pelvic pain; nearly half of these had undergone prior pelvic irradiation for treatment of a malignancy. Thirty-nine percent of the patients had some improvement in their walking ability.

There are important limitations of this study. This was a retrospective review of one surgeon's experience at two institutions. The variety of pathology treated and of surgical techniques used makes it difficult for the authors to recommend the optimal surgical management of these patients. The lack of a validated functional outcome score makes accurate interpretation of the results difficult given this highly complex patient population. However, the authors did demonstrate that union after pathologic and insufficiency fractures can be achieved and that some of the patients can have improvement in their functional status.

The procedures described in this paper are technically demanding and should be performed by surgeons experienced in the management of pelvic injuries. Surgery should be considered only in the case of symptomatic nonunions after nonoperative treatment has failed. The pathological nature of the bone and soft tissues adds significant risk and complexity to the surgery. Recent developments in methods of percutaneous fixation of pelvic injuries may simplify the management of these problems^3-5, which, fortunately, remain uncommon.

*The authors did not receive grants or outside funding in support of their research or preparation of this manuscript. They did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.

References

1. Pennal GF, Massiah KA. Nonunion and delayed union of fractures of the pelvis. Clin Orthop. 1980;151:124-9.
2. Koval KJ, Aharonoff GB, Schwartz MC, Alpert S, Cohen G, McShinawy A, Zuckerman JD. Pubic rami fracture: a benign pelvic injury? J Orthop Trauma. 1997;11:7-9.
3. Altman GT, Altman DT, Routt ML Jr. Symptomatic hypertrophic pubic ramus nonunion treated with a retrograde medullary screw. J Orthop Trauma. 2000;14:582-5.
4. Starr AJ, Jones AL, Reinert CM, Borer DS. Preliminary results and complications following limited open reduction and percutaneous screw fixation of displaced factures of the acetabulum. Injury. 2000;32 Suppl 1:SA45-50.
5. Zura RD, Kahler DM. Transverse acetabular nonunion treated with computer-assisted percutaneous internal fixation. A case report. J Bone Joint Surg Am. 2000;82:219-24.