In the present prospective study, 25 adults having compound tibial shaft fractures of Gustilo Type I, Type II and IIIA were managed with antibiotic impregnated IM nails, at a tertiary institute of Punjab, India from June 2018 to May 2019. They were evaluated for the outcome. This research was approved by the Ethical Committee (GMC/1048/2k18) of the institution and was done after having patient’s consent for their involvement in the study.

History regarding mode and mechanism of injury was documented followed by standard emergency evaluation and investigations. Wound irrigation of open fractures with three litres of normal saline, debridement and primary suturing was performed where possible. Plaster of Paris (POP) back splintage and sending cultures was done as initial measures in those cases that didn’t report to institution within the recommended golden period of six hours and more when the edges of their wounds were soiled due to road side accidents. If the cultures were sterile, the patient was posted for surgery; if not, patient was put on parenteral antibiotics, depending upon growth and sensitivity of organism, in recommended dosage as per literature till his cultures showed no growth and Erythrocyte Sedimentation Rate (ESR) and Connective Tissue Reactive (CRP) levels returned to normal. Thereafter, the patients were planned for surgery. Although it increased the hospital stay for a few more days, but it was worth it. X-rays were done in two views. All the patients were operated under spinal anaesthesia with standard nailing technique. Commercially available cytocompatible Gentamicin eluting tibial nail was used. It is a nail with double coating (to provide better adhesion as compared to dip coating) of the antibiotic, with a coat thickness of 50 micron measured by Scanning Electron Microscopy (SEM). The manufacturer provided the uniform coating of antibiotic over the nail by high velocity spray coating technique. The concentration of the drug in it was 1 mg. per square cm. Total drug on an average size nail was 100 mg. The drug postoperatively released with an initial burst of 30-40% in first 3-4 days with an initial highest concentration locally up to 200 microgram/ml which prevented and destroyed the colonsation of invading bacteria. This was followed by the sustained release of the antibiotic for another 4-8 weeks maintaining local drug levels high enough for the bactericidal activity in a period, most susceptible to infections postoperatively.

X-rays were done postoperatively to confirm the adequacy of reduction. Parenteral broad spectrum antibiotics {cefuroxime (1.5 gm BD+ amikacin (25 mg/kg) BD} were given for initial seven days and then, switched over to oral antibiotics for another seven days. Static exercises commenced on the second day and touchdown weight bearing with walker allowed on third postoperative. day. Sutures were removed on 10^th postoperative day. All the cases were followed-up in the Out Patient Department (OPD) at six weeks, 12 weeks and six months and thereafter at regular intervals until clinical and radiological union occurred.

Time of union: Clinical signs of union were taken as no pain, warmth or redness at the fracture site and unrestricted weight bearing. Radiological signs of union included appearance of callus in three out of four cortices, obliteration of fracture line, homogenous bone structure, trabecular and cortical continuity. Following arbitrary standards of rate of union were adopted: Normal union 12-20 weeks; Accelerated union <12 weeks; Delayed union >20 weeks. Radiological union was achieved in 12 to 18 weeks (average 15.55 weeks) in all AO group A, group B fractures with Gustilo type I injury [Table/Fig-1]. Complex AO group C with Gustilo type II took 12 to 22 weeks (average 16.69 weeks) [Table/Fig-2] for radiological union.

[Table/Fig-1]:

Catalogue of implant used. a,b) Preoperative X-rays (ap and lateral) showing AO group A fracture (gustilo type I); c,d) Postoperative X-rays (ap and lateral) showing uniting fracture in AO group.

[Table/Fig-2]:

a) Preoperative wound (gustilo Type II); b) Healed wound; c) X-ray of complex AO group C (gustilo type II) showing united fracture.

Results were graded as excellent, good, fair and poor as per Lysholm criteria [15] [Table/Fig-3] to assess postoperative functionality of the knee joint [Table/Fig-4,5]. Results were graded as-

[Table/Fig-3]:

Lysholm criteria [15].

[Table/Fig-5]:

Postoperative functionality at knee joint.

The results of observations of individual patients were pooled. Data collection, compilation and analysis performed using microsoft excel 2007 (any type of statistical analysis was not needed, so simple percentage values were calculated using Microsoft excel 2007).

A union rate of 100% was achieved in present study with 92% excellent to good results, as per lysholm scale [Table/Fig-6]. Partial weight bearing commenced at 5.44 weeks on an average and full weight bearing on an average after 10.48 weeks of surgery. Only six out of 25 cases needed eradication of infection (superficial in five and deep in one case) with systemic antibiotics for more than stipulated period and eventually increasing the union time.

The patients advised follow-up visits at 6, 12, 24 weeks and thereafter, at six months to assess the progress of union radiologically, wound condition and for implant failure if any. The shortest time to union was 12 weeks in group A fractures with Gustilo type I injury and longest was 22 weeks in group B with Gustilo type II fracture. There was one case with Gustilo type IIIA fracture which showed delayed union (beyond 22 weeks) due to infection along the deeper tissue planes in that case.

With regular physiotherapy and active movements of knee, full range of flexion returned in all cases. After about five weeks of active movements of ankle, all patients had near normal or normal range of ankle movement. There was no clawing of toes postoperatively. There was no case of fat embolism/ amputation of limb/ postoperative death.

In the present study, 25 cases of compound factures of the tibia were treated with antibiotic impregnated tibial nail. In present series, 80% of the fractures were due to high velocity road traffic accidents, 12% were due to fall and 8% were as a result of direct trauma. This was comparable to earlier studies [16-18].

Various researchers have documented the importance of local elution of antibiotic as a game changer for achieving union in compound fractures of tibia. Raschke MJ et al., quoted that an IM tibia nail with antibiotic coating proved to be a useful tool in the treatment of tibia fractures in patients with a higher risk of developing implant-related infections. Gentamicin impregnated tibia nail reduced deep infections and prevented long-term external fixation [19].

Thonse R and Convey J treated infected non-union and segmental bone defects of tibia with antibiotic cement-coated interlocking nail. They managed 20 patients by this and found that 17 (85%) patients, got bony union. Three patients (15%), had control of infection with stable non-union (one patient) and stable non-union with cement spacer (two patients). Nineteen (95%) patients achieved control of infection except for one patient, who had a bony union with intermittent wound discharge finally landing in above knee amputation. Three patients (15%) needed exchange nailing to another antibiotic cement-coated nail in order to achieve infection free union [20].

Metsemakers WJ et al., treated 16 consecutive patients with 16 tibia fractures from a gentamycin-coated IM nail. Among them, 11 (68.8%) with acute fractures were treated with a gentamicin-coated IM nail; rest five were complex revision cases (31.2%). No deep infections noted after the treatment with a gentamicin-coated tibia nail [21].

Bharti A et al., postulated that local antibiotic delivery system through antibiotic impregnated Poly Methyl Methacrylate (PMMA) rods holds a promising modality of treatment for handling difficult to control, chronic infections and promotes bony union. They achieved union in five patients (71%) at mean follow-up of 7.28 months. No infection was there in six cases (85.7%), out of which four cases (57%) had good union and two had (29%) had a non-union. One case was of infected union (14.5%) [22].

Bhatia C et al., concluded that antibiotic cement impregnated nailing is simple, economical and an effective single stage procedure for the management of compound tibial fractures with non-union. They controlled Infection in 95% of the patients and achieved bony union in 60% patients with antibiotic cement nailing [23].

Desouuza C et al., also documented the role of cement coated antibiotic nail in compound fractures of tibia with bony non-unions and advocated its use. There was no infection in 95% of the patients and bony union was achieved in 60% patients with antibiotic cement nailing with average time of union of 32 weeks [24].

In the present study, results were better when compared with above quoted studies as 100% union achieved with overall infection rate of 24% only. Infection did not hinder the union and resolved with local antibiotic release through nail and concurrent administration of systemic antibiotics.

The small size of the sample and affordability of the implant were the limitations of the present study. More studies on a larger data base are needed to corroborate findings of the present study.

Antibiotic impregnated nailing is a very effective single stage procedure for the management of gustilo type I, II, IIIA compound fractures of tibia. It achieves the goal of early bony union with less morbidity and decreases the complications such as infection and chronic osteomyelitis due to constant elution of antibiotic at the fracture site, obviating the need of intravenous/oral administration of the same, thus decreasing the overall systemic side effects. It also decreases the non-union percentage as the fixation is sound in the absence of infection and enhances the bone formation rate and eventual early fracture union. Also, early range of motion exercises of joints and early weight bearing is permitted because breakage of implant is very uncommon due to load sharing.