Fractures of the acetabulum remain an enigma for the orthopaedic surgeon [21
]. This 10-year-old statement is still applicable in the developing world, due to the lack of technical expertise and inadequate infrastructure. The trend is, however, changing because of the easy access of information technology and the international literature. The standardisation of clinico-radiological evaluation, fracture classification, surgical approaches and fixation techniques of displaced acetabular fractures has resulted in achieving the goal of preserving a functional, mobile and painless hip joint [17
It is an accepted fact that the functional results of the displaced acetabular fractures correlate well with the quality of reduction and that open reduction is the best method to achieve congruity [3
]. In our series also, radiographic congruity (76.19%) correlated well with the function (74.6%) (Table ). The quality of reduction in our study decreased with the increase in the complexity of the acetabular fracture. Radiologically, 86.66% (13 out of 15) of simple fractures and 72.91% (35 out of 48) of complex fractures had congruent reduction. Correlating well with the congruity, 80% (12 out of 15) of the simple fractures and 72.91% (35 out of 48) of the complex fractures had excellent/good function (Harris Hip Score>80). Overall, 74.6% of our patients had excellent/good results (Harris Hip Score>80). Table compares our results with the other reported series [4
Comparison of radiological and functional evaluation between the early and late operated cases
The most common approach used by us was that of Kocher-Langenbeck in about half of the patients (47.6%). In the early phase of our learning curve, probably due to greater familiarity with this approach only, it was used more commonly, even in some complex fractures, when we used to supplement the complex fractures by skin traction for 3–4 weeks because there was no anterior fixation. Gradually, as we became accustomed to the acetabular anatomy, we shifted to the ilio-inguinal approach for anterior wall/column fractures. Lately, all complex bicolumnar fractures requiring bicolumnar fixation were managed by a combined approach undertaken during single-stage surgery.
We believe that the anterior opening of the pelvic ring in the case of a floating acetabulum (Fig. a) is not associated with injury to the anterior interossious sacroiliac ligaments, which is, otherwise, a standard pathology associated with pubic diastasis. This pathology in the floating acetabulum is substituted with the displacement at the fractured acetabulum as the force is spent at the acetabular fracture; during surgery, reducing the acetabular fracture lead to a spontaneous reduction of the pubic diastasis, which was then stabilised with a plate (Fig. b).
During surgery, the drill bit was broken in eight patients (12.91%). All of the broken drill bits were locally manufactured and were broken during the drilling in the supra acetabular area above the pelvic brim (Fig. ). Lately, we have been using 2.5-mm K wire for drilling the holes in this area instead of a drill bit and we are now able to avoid this complication.
Five patients (7.93%) had heterotopic ossification. The use of osteotomies, the amount of subperiosteal stripping and the severity of fracture predisposes to heterotopic ossification [1
]. Two of the five patients with heterotopic ossification had a complex fracture anatomy, while the remaining three had presented to us at 15, 18 and 90 days of injury, resulting in the delayed operative intervention, leading to more handling and stripping of tissue at surgery. We now routinely use prophylactic indomethacin 75 mg twice daily for 4 weeks in the patients operated after a delay of more than 2 weeks.
In our series, the infection rate was 7.93%, which was higher than reported in other studies (0–3%) [2
]. Of these patients, 80% (4 out of 5) were operated upon during our learning curve period. In three patients, the indigenously produced cheaper implants had been used. All of these patients were treated more than 2 weeks after injury (15, 16, 18, 22 and 28 days). Of these, two had been operated by a tri-radiate approach, two with extended ilio-femoral approach and one with the Kocher-Langenbeck approach. One patient was operated with a combined approach that developed deep infection in the posterior wound. Four patients made complete recovery after wound debridement and antibiotics. A 56-year-old diabetic, treated via an ilio-inguinal approach on the 28th day of injury, underwent debridement for deep infection at 4 weeks of surgery. At 1 year follow up, the routine X-ray showed non-union of the fracture with sclerosed margins and broken plate (Fig. ). The other factor of failure in this patient may be attributed to the use of a cheaper locally made implant. In India, due to the lack of an organised insurance sector, the cost of the implant is bourne by the patients. Although as a matter of routine we offer to the patients implants manufactured by internationally accepted manufacturers, yet, in some patients, we use the locally made more affordable implants.
The incidence of avascular necrosis was quite low in our series (2 of 63), probably because, during the posterior approach, we approach the fractured acetabular fragment from the iliac/ischial side. The capsule is only opened if reduction is not achievable without opening the capsule or, pre-operatively, there is evidence of an intra-articular loose bony fragment. We feel, however, that the minimum follow up in our study being 26 months, there may be some patients who develop radiological evidence of avascular necrosis at a later stage.
Two patients developed iatrogenic sciatic nerve injury, which recovered partially with time. A 20-year-old labourer with posterior fracture dislocation was treated on the 24th day after injury due to late presentation. Probably, excessive traction during reduction or the pressure of a Hohman retractor in the greater sciatic notch resulted in concussion to the nerve. The patient showed complete recovery at 3 months. The other patient had suffered a posterior fracture dislocation, along with fracture of the shaft of the femur. His femoral shaft fracture was treated by intramedullary nailing outside our institution 3 months earlier when closed reduction was performed for acetabular fracture. At 2 months, the patient underwent open reduction for the persistent unreduced dislocation by the same surgeon. After the second operation, the patient developed a foot drop. At a total of 3 months after injury (one month after second operation), the dislocation was still seen to be unreduced associated with persistent foot drop. The patient was referred to us at this time. CT scan of the patient (Fig. b) showed a dislocated femoral head posteriorly and an intra-articular fragment. The missed intra-articular fragment at the time of the previous surgery was probably the cause of the unreduced dislocation. At surgery, we found fibrosis in the tissue planes and it took us time to dissect the sciatic nerve (Fig. a). Finally, at 48 months follow up, the patient had zero power in extensor hallucis longus and grade 3 power in the other dorsiflexors, while the plantar flexors were unaffected. Radiologically, the fracture had uneventful healing (Fig. c).
a Intact sciatic nerve in neglected unreduced dislocated head with previous surgery resulting in sciatic nerve injury. b Pre-operative CT scan showing intra-articular fragment and dislocated femoral head. c Final follow up X-ray of the same patient
The surgical treatment of acetabular fractures, in the cases presenting late after the accident, is difficult but, nevertheless, possible. The total joint replacement, if needed subsequently, in such cases is much simpler [16
]. We found that complications like sciatic nerve palsy and heterotopic ossification, as well as infection, were more commonly observed in the patients who were operated upon after a delay of more than 2 weeks. Brueton [3
] reported that the results were inferior if the patients were treated with an average delay of 17 days after the injury and recommended a rapid referral to a regional centre with the necessary facilities and expertise to manage displaced acetabular fractures.
Additionally, we observed that the patients in whom locally manufactured implants and drill bits were used suffered a higher rate of complications, such as broken drill bits (all eight cases), broken plate (only one case) and infection (3 of the 5 cases). Thus, we feel that the patients presenting late and being operated after a delay of over 2 weeks, and the patients opting for low-cost locally manufactured implants should be informed about the higher risk of these complications at the time of giving their consent.
In conclusion, the operative treatment of displaced acetabular fractures gives universally satisfactory results. The surgeons should prepare well for problems such as prolonged operating time and increased blood loss, more so in the learning curve phase and in the patients operated after a delay of over 2 weeks. Time spent on a thorough study of the radiographs and a proper pre-operative plan helps to outline an appropriate surgical approach and the appropriate type of implant. A higher risk of complication should be explained to the patients opting for low-cost locally manufactured implants and to the patients undergoing surgery after a delay of over 2 weeks. In addition, health planners should be apprised of the need for provision of high-quality implants to all patients, irrespective of their socio-economic status.