A Prospective Comparative Study of Reamed vs . Unreamed Nailing in Fractures Shaft of Tibia

Background: Although the tibia is one of the most commonly fractured long bones in the body, there are two accepted management techniques: reamed and unreamed nailing. There is not a general consensus as to which technique is more advantageous to the patient. Patients and methods: This was a single centre prospective randomized trial of 38 adults with a tibial shaft fracture who were treated with either reamed or unreamed nailing. Results: Overall fracture healing time was 23 weeks in the reamed group and 25 weeks in the unreamed group. Differences in rate of clinical union, clinical outcome, time for weight bearing and complications in both the groups were not statistically significant. Conclusion: There are no clear indications or contraindications to favour either reamed or unreamed nailing over the other. Technique, fracture union, functional outcome and complications are similar in both groups. Considering the ease of technique application and the decreased operative time, unreamed interlocking nailing has an edge over reamed interlocking nailing.


INTRODUCTION
The tibia is one of the most commonly fractured long bones in the body and a major cause of morbidity 1,2 .These fractures pose a serious problem because of their subcutaneous location and precarious blood supply and resultant problems in union.Trauma surgeons have not yet reached a consensus on a single treatment protocol for all patients with tibial shaft fractures.Fractures of the tibia cannot be treated successfully in all cases with only one approach or a single simple set of rules [2][3][4] .In this study, two modalities of fixation of shaft of tibia fractures were chosen and compared: 1) reamed interlocking intramedullary nailing; and 2) unreamed interlocking intramedullary nailing

PATIENTS AND METHODS
A prospective randomized comparative study was conducted to evaluate technique, outcome and time to clinical and radiological union following reamed vs. unreamed interlocking nailing.Advantages, disadvantages, follow up and complications if any and overall functional outcome were evaluated.Clinical and radiological follow-up took place in the immediate postoperative period and subsequently at periodic intervals enabling comparison of the two techniques.
Thirty-eight patients with tibial shaft fractures treated in the Department of Orthopaedics, Rajah Muthiah Medical College and Hospital, Annamalai University, Chidambaram, admitted from May 2009 to May 2011 comprised the study group.Skeletally mature patients were chosen for the study and comparisons were made after treating the fractures with either reamed or unreamed interlocking nails.Skeletally immature patients, fractures extending to an articular surface, fractures with neurovascular injuries and pathological fractures were excluded from the study.
In cases of open fractures, thorough wound debridement was performed in the emergency theatre on the day of admission.Antibiotic prophylaxis and tetanus prophylaxis were administered and wound dressing was performed; internal fixation was undertaken at an appropriate time.All fractures were classified according to AO classification for diaphyseal fractures of tibia.The degree of comminution was assessed according to Winquist and Hansen's classification 5 .In closed fractures, the Tscherne and Gotzen classification 6 for soft tissue was used.
All the patients underwent fracture fixation under spinal/epidural anaesthesia.Patients were placed on the fracture table with the injured leg bent at 90 degrees at the knee with the help of a padded attachment 7,28 and tourniquet 8 for all cases.An anterior midline patellar ligament splitting approach was used for both techniques.Nail length was measured preoperatively and the most commonly used nail diameter was 9 and 10mm.
For the reamed group, reaming was carried out for the entire extent of the medullary canal in a sequence of 0.5-mm increments using flexible reamers.The canal was reamed to 1mm more than the diameter of the nail.The appropriate length of the nails that were to be inserted after reaming was determined with use of the guide-rod subtraction method.In the unreamed group, reaming was limited only to the proximal 6 to 8 cm of the metaphysis to accommodate the proximal flare of the nail.The diameter of the nail was determined by the measurement of the narrowest diaphyseal diameter of anteroposterior and lateral radiograph.
Insertion of the nail was controlled under image intensification.Whether to provide static or dynamic locking and the number of interlocking screws were determined according to fracture geometry.Proximal interlocking was carried out with the aid of nail mounted targeting devices, whereas distal interlocking was carried out with a freehand technique under an image intensifier.

RESULTS
The average operating time for reamed nailing was 70 minutes and the average operating time for unreamed nailing was 55 minutes.The patients were evaluated immediately post op, six weeks, six months and one year after surgery.There were 30 male and 8 female study participants with an average age of 25 years (range, 21-30y).Twenty-three patients had right sided injuries while 15 had left sided injuries, and high velocity motor traffic accidents were the most common cause of injury.Alternating cases were treated with either reamed or unreamed interlocking nailing of the tibia to simulate a randomized controlled trial.
Twenty cases were treated with reamed nailing while 18 were treated with unreamed nailing.There were 16 AO type A fractures, 11 type B and 11 type C fractures.Based on the Winquist and Hansen classification, 22 cases were type I, 10 were type II, 5 were type III and one was type IV.Eleven fractures were located in the upper third of the tibia, 13 were in the middle third and remaining 14 were in lower third.
There were 6 open fractures in the reamed group and 3 open fractures in the unreamed group (Table I).
Outcomes including complications encountered, rate of clinical union and rate of radiological union were documented and compared between the reamed and unreamed groups using the Johner and Wruh's criteria 9 .
There were no significant differences in patient age, gender, mode of injury or overall distribution of fracture types between the reamed and unreamed groups.The average time to clinical union in the reamed group was 20.5 weeks.One patient did not show union by 26 weeks.Average time to clinical union in the unreamed group was 22.5 weeks.The average radiological union in the reamed group was seen at 23 weeks and one patient did not show radiological union beyond 28 weeks.In the unreamed group the average radiological union time was 25 weeks.
In the reamed group, out of 20 cases, six developed complications.There was one case of nonunion 11 , one case each of superficial infection 10,11,29 , screw breakage 12 , knee stiffness, ankle stiffness and knee pain 13 .In the unreamed group, out of 18 cases, 5 cases developed complications.There was one case of external rotation deformity, one case of knee stiffness, 2 cases of ankle joint stiffness and one case of knee pain 13 .

DISCUSSION
The tibia is one of the most commonly fractured bones in the body and intramedullary fixation of tibial shaft fractures has gained popularity in recent years with the development of interlocking nails.This technique is currently used to stabilize unstable diaphyseal tibial fractures.However, differing surgeons advocate two different methods of nail insertion, i.e., with and without reaming of the medullary canal.Each method has specific advantages and disadvantages and controversy still continues regarding which method is warranted for specific clinical situations.While reaming can cause devascularisation of the cortex and thermal necrosis of the inner 50-70% of the cortex 14,15 thus delaying healing, it can also help to fix the fracture with a larger size nail thus achieving better stability 16,25,26,30 .The effects of reaming on fat embolism should also be considered.
In unreamed nailing, there is less risk of fat embolism and several studies suggest better preservation and more-rapid recovery of the intraosseous blood supply after insertion of a small-diameter nail without reaming [17][18][19][20][21][22] .In contrast, studies by Blachut et al. 23 and Court Brown et al. 24 seem to indicate that nonunion occurs more frequently with unreamed nailing 17,25,26 .Some studies indicate increased incidence of screw breakage with unreamed nailing 23,27 .
In the present study, there were sixteen AO type A fractures.Out of these 16, twelve fractures showed excellent results, three fractures showed fair results and one showed poor results.Eleven cases had AO type B fracture and of these, seven cases had excellent results, one case had good results, one case had fair result and two cases had poor results.Eleven cases had AO type C fractures and of these, ten cases had excellent results while one case had good results.
Among the reamed group, ten cases had AO type A fracture out of which seven cases showed excellent results, two cases showed fair results and one case showed poor results.The overall outcomes in this study showed 80% good to excellent results with reamed interlocking nailing, whereas we found 72.22 % good to excellent results with unreamed interlocking nailing.The type of fracture did not significantly alter the outcome.The pattern of fracture was similar in both groups.The age distribution was identical.A majority of t patients, 30 of 38, were males.As the number of female patients was only 8, distributed as 4 in each group, we conclude that gender difference did not play a role in final outcomes.
Although, theoretically reaming increases the risk of fat embolism, no such reports are evident in clinical setting.
Though some studies indicate that nonunion occurs more frequently in unreamed nailing, that did not seem to be the case in this study.

CONCLUSION
Intramedullary nailing is the proven choice of treatment for adult tibial shaft fractures, despite the fact that controversy exists regarding the choice of reamed or unreamed intramedullary nailing.There are no clear indications or contraindications for choosing either option.
The rate of clinical and radiological fracture union, functional outcome and complications were similar in both the study groups.Considering the ease of performing the technique and the decreased operative time, unreamed interlocking nailing may have an edge over reamed interlocking nailing.

Table I :
Anatomical parameters of Atlas Based on the Winquist and Hansen classification, there were a total of twenty two Type I fractures, out of which sixteen cases had excellent results, one case had good results, three cases had fair results and two cases had poor results.Ten Winquist and Hansen type II fractures were present out of which one case had poor results and nine cases had excellent results.Winquist and Hansen type III fractures were seen on five cases out of which one case had good results and one case had fair results with the remaining three cases having excellent results.There was only one Winquist and Hansen type IV fracture and it had excellent results.Among the reamed group, there were twelve Winquist and Hansen type I fractures, out of which two cases had fair results and one case had poor results leaving nine cases with excellent results.There were six Winquist and Hansen type II fractures, out of which one case had poor results and five had excellent results.There were two cases of Winquist and Hansen type III fracture both of which had excellent results.There were no cases of Winquist and Hansen type IV fractures in the reamed group.In the unreamed group, there were ten Winquist and Hansen type I fractures out of which seven cases had excellent results, one had good results, one case had fair results and one case had poor results.There were four Winquist and Hansen type II fractures and all four had excellent results.Three Winquist and Hansen type III fractures were present out of which one case had fair results, one case good results and one case had excellent results.There was one case of Winquist and Hansen type IV fracture which had excellent results.