Uncoiling of Flexible Reamer during Closed Nailing for Shaft Femur Fracture

INTRODUCTION

The shaft of femur fractures in adults are a common and serious orthopedic event, managed mostly by intramedullary interlocking nails (IMILN).¹ With the advent of reaming prior to nail insertion, a larger-diameter nail can be inserted, which additionally provides bone graft, enhancing union.^1,2 Ill effects of reaming in terms of heat necrosis and damage to endosteal blood supply have been elaborately studied and newer designs of reamers with narrow shape and sharper flutes have been developed to minimize these complications.^3–5 Increased chances of pulmonary embolism have also been documented.^2,6 Complications have also been reported in terms of hardware failure and breakage during reaming.⁷

We present a unique case of hardware malfunction where uncoiling of the reamer shaft occurred during the procedure for a case of femoral shaft fracture. This is a rarest of rare event that has only been reported once, prior to the present case.

CASE DESCRIPTION

A 21-year-old male presented to the advanced trauma center of our institute, in severe pain in left thigh and inability to bear weight on the left lower limb following a road traffic accident 5 hours ago, when the motorcycle he was driving collided with the road divider, and he fell off subsequently. He had a helmet on and had no history of any loss of consciousness or bleeding from ear, nose, or throat.

He was unable to stand and was brought in on a stretcher. He had gross deformity and swelling on his left thigh. There was no bruise or visible injury marks on the skin. The distal neuromuscular status was intact. The other three limbs were not injured. The patient was given the oxygen support via a venti mask, intravenous fluid was started, arterial blood gases were tested, routine blood workup with hemogram was done, and input/output monitoring was initiated. The limb was elevated and stabilized on a bohler braun (BB) splint and plain radiographs were done. A femur shaft fracture was diagnosed (Figs 1 and 2). An upper tibial pin was inserted and the patient was given skeletal traction on a BB splint.

He was taken up for surgery for a reamed interlocking nail (ILN). The preoperative templating revealed a canal size of 10 mm and 40 cm length of the nail. The patient was placed supine on a fracture table. After the routine painting and draping, a greater trochanteric entry was made under the C arm guidance. A ball-tipped guidewire was inserted and after reducing the fracture, it was advanced into the distal fragment.

Reaming was started with a flexible reamer size 8 mm using a power drill. Subsequently, 8.5- and 9-mm reamers were used. During reaming with a 9.5-sized reamer, at the isthmus, gross resistance was felt. The reamer could not be advanced and it got stuck. On attempting to withdraw, the shaft of the reamer started uncoiling (Figs 3 and 4). The handpiece was detached and a T handle was attached to the proximal end of the shaft. With gentle blows from a hammer on the T handle, the reamer was withdrawn along with the guidewire. The central part of the shaft of the reamer had completely uncoiled over the guidewire (Fig. 5). The surgery was resumed with reinsertion of another guidewire and a nail of length 40 cm and 10 mm diameter was inserted (Figs 6 to 8) Postoperatively the patient did fine, was started with partial weight bearing followed by full weight bearing at 4 weeks, and at 4 months’ follow-up he had complete fracture union.

DISCUSSION

The closed IMILN for femoral diaphyseal fractures is a standard practice that does not drain the fracture hematoma or damage any soft tissue attachments. A reaming material in the medullary canal acts as bone graft with osteogenic properties, enhancing bone union.^1,2

Intraoperative complications in orthopedic surgeries are unpredictable and occur even in best of hands. There have been reported cases of breakage of the reamer during nailing, or its incarceration during the procedure.^7,8 Uncoiling of the reamer is a rarest of rare complication and we highlight its possibility and analyze the factors that could lead to such an event.

Flexible shafts of the reamer are made of coaxially arranged wires that are coiled.⁹ With the aid of a handheld power source, it is advanced with a clockwise movement. Movement in the opposite direction could lead to uncoiling.⁹ However, in the present case, uncoiling did occur without an opposite movement of the shaft.

During the reaming procedure, increased resistance is felt at either the isthmus of the canal or the fracture site. There could be a tendency on part of the surgeon to add some extra effort and push through that resistance. In a similar case reported by Meena et al., uncoiling occurred because they started reaming directly with a larger-sized reamer and when they tried to withdraw the stuck reamer, the coiling increased.⁹

In the present case though, reaming was sequential and the probable cause could have been incarceration, which is a complication reported by Low et al.⁸ The reaming debris could collect around the flutes of the reamer and this could lead to its incarceration.⁸ If attempt is made to forcibly withdraw the reamer, there is a possibility of twisting of the coil and subsequent uncoiling. This could have happened in the present case. So, during reaming, the force should be moderate and intermittently the reamer should be withdrawn a little to clear up the debris.⁹

We were able to remove the uncoiled reamer by back hammering. The ball-tipped guidewire was an important aid for removing the incarceration due to the debris. The reamer used in the present case had been previously used in other cases. That could have led to its wear and tear and could have been another reason for the uncoiling when it encountered resistance and increased force.

So, this complication requires awareness especially if the hardware used is not new, and importance of shelf life is paramount. Such implants should not be used for repetitive surgeries in view of complications like breakage or uncoiling.

CONCLUSION

Uncoiling of a flexible reamer is a rare but possibly catastrophic complication. The importance of sequential reaming and moderate force during the procedure is immense. Despite proper precautions, complications do occur, even in experienced hands, but one should be careful and perform these surgeries, step by step under extreme vigilance and zero complacence.

REFERENCES

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2. Selvakumar K, Saw KY, Fathima M. Comparison study between reamed and unreamed nailing of closed femoral fractures. Med J Malaysia 2001;56 (Suppl D):24–28.

3. Leunig M, Hertel R. Thermal necrosis after tibial reaming for intramedullary nail fixation. A report of three cases. J Bone Joint Surg Br 1996;78(4):584–587. DOI: 10.1302/0301-620X.78B4.0780584.

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6. Pape HC, Auf’m’Kolk M, Paffrath T, et al. Primary intramedullary femur fixation in multiple trauma patients with associated lung contusion–a cause of post traumatic ARDS? J Trauma 1993;34(4):540–547. DOI: 10.1097/00005373-199304000-00010.

7. Rijal L, Manandhar H, Nepal P, et al. Instrument fails, but surgeon should not. Surgical techniques for retrieval of broken intramedullary reamer from tibia. Eur J Orthop Surg Traumatol 2010;20(6):505–507. DOI: 10.1007/s00590-010-0591-y.

8. Low TH, Loke YH, Chiu CK. Minimally invasive retrieval of incarcerated flexible intramedullary reamer. Eur J Orthop Surg Traumatol 2012;22 (Suppl 1):113–115. DOI: 10.1007/s00590-012-0995-y.

9. Meena S, Trikha V, Singh V, et al. Uncoiling of reamer during intramedullary nailing for fracture shaft of femur. J Nat Sci Biol Med 2013;4(2):481–484. DOI: 10.4103/0976-9668.116985.