Evaluation of Diaphyseal Tibial Alignment Following Intramedullary Nail Fixation at Knh

Abstract

Background: Intramedullary nailing (IMN) is an approach of fracture fixation and performed since early 20th century. Owing to the variations in type of complications related to fractures of tibia, intramedullary fixation has allowed opportunities for further improvement. Significant complexities exist in management of diaphyseal tibia fractures with a higher risk of mal-alignment. This contributes to significant disability in patients, declined quality of life and escalates the costs of treatment. Furthermore, there is a disruption of otherwise normal joint kinematics resulting in non-physiologic loading of the knee and ankle leading to significant limitation of function, causing a deformity across the knee and tibiotalar joint resulting in alteration of overall joint biomechanics and post-traumatic arthritis thus limiting both ankle and knee range of motion with gait disturbance. Extremely small amounts of persisting angulation in the fracture that is already united, and as minute angulation as possible, changes the load across the knee and ankle joints. Improved biomechanical understanding of diaphyseal tibia malalignment will help to formulate improved treatment modalities and should be minimized whenever possible. Objective: The main aim of this study is to evaluate diaphyseal tibial alignment following intramedullary nail fixation at the Kenyatta National Hospital. Methods and Materials: The study was a cross-section analytical in design involving 72 patients, carried out Kenyatta National Hospital, Orthopedic and radiology imaging Departments. Patients who presented to KNH with Diaphyseal tibial fractures to undergo Intramedullary Nailing (IMN) were recruited into the study. Outcome measures were malalignment, elaborated as varus/valgus angulation (anterior/posterior angulation) of knee xiii at 5 degrees and sagittal angulation of 10 degrees bases on first anteroposterior and lateral X-rays after fixation surgery. Direct clinical measurements of limb length discrepancy for both injured and uninjured limb were taken and the measurement documented. Results: Seventy-two patients undergoing diaphyseal tibial fracture fixation, and treated with an intramedullary nail, were consecutively recruited. The respondents were aged between 19 and 59 years of age. The mean age was 31years and 6 months (95% CI; 29.5 to 33.5). The majority of the respondents were male (n=66; 91.7%) and 6 (8%) women. Majority of the patients (n=48; 66.7%) had open fractures and 24 (33.3%) closed fractures. Using AO fracture classification two thirds of the respondents (n=49; 68.1%) had Middle level of fracture, 17 (23.6%) had Lower Level while only six (8.3%) had Upper level. Approximately 42% (n=30) of the respondents had simple transverse fractures(42A3), 31% (n=22) sustained oblique fractures(42A3) and 17% (n=12) comminuted fractures(42B3), complex segmental 4(5.6%), (42A1) simple spiral 4(5.6%). Approximately 92% (n=66) had fibula fractured but not Plated, with 7% (n=5) being intact and only one patient presented with fibula fracture and plated. Two thirds (n=48; 66.7%) were attended by Registrars while a third (n=24; 33.3%) were attended by the Consultants (figure 10). Majority of the patients (n=49; 68.1%) underwent a closed surgical procedure while the rest underwent open surgical procedure. Localization of the entry point was through eye balling in approximately 82% (n=59) of the cases, the others were through Image intensifiers (fluoroscopy). Gravity and manual Traction as a method of achieving reduction was used in approximately 96% (n=69) of the Cases. The most preferred method of maintaining the reduction was Gravity and manual traction at 68.1% (n=49). Manual traction, gravity and clamping was used in 31.9% (n=23) of the cases. The most utilized nail sizes for fracture reduction were 36*10mm, 34*10mm and 36*11mm at 38.9%, xiv 37.5% and 13.9% respectively. Nail size 36*9mm was used in 4.2%, nail size 34*9mm, in 2.8% and nail size 34*11mm and 32*10mm in 1.4% each. In 58.3% (42) of the cases, a reaming diameter of 2mm was used. A reaming diameter of 1mm was done in 25 (34.7%) cases. The overall rate of malalignment was 6.9% in length discrepancy and 1.4% malalignment in sagittal plane. with upper and lower third fractures most affected by malalignment. No middle third fractures had malalignment. Location of fracture, predicted the occurrence of malignment with a p value of 0.001. There was no association between entry point and malalignment. Conclusion: Middle third diaphyseal tibial fractures can be treated adequately with eyeballing technique, manual traction and gravity as a method of achieving and maintaining reduction and compared to upper and lower third fractures which require use of fluoroscopy to minimize the risk of malalignment. This would help optimize the use of fluoroscopy in the hospital which is a scarce resource.