Functional outcome of distal femur fractures in Hospital Tengku Ampuan Afzan, Kuantan, Pahang

Abstract

Objective: This study was designed to evaluate the functional outcomes of patient with distal femur fracture treated operatively. Methods: 105 cases of distal femur fracture were treated surgically in Hospital Tengku Ampuan Afzan from January 2010 to December 2013. 61 out of 105 patients (58%) were followed-up with minimum period of 6 months and evaluated for the functional (Lysholm score), quality of life (SF36) and radiological (Rasmussen anatomical radiological score) outcomes by a series of questionnaire and measurement. Result: There were 49 males (OTA type 33-A=14, OTA type 33-B=13, OTA type 33-C=22) and 12 females (OTA type 33-A = 6, OTA type 33-B = 2, OTA type 33-C = 4) with ratio being 4:1 (male: female). Average age was 39.5 years in OTA type 33-A, 31.9 years in OTA type 33-B and 36.8 years in OTA type 33-C. There were 7 patients with Type 33-A1, 9 patients Type 33-A2, 4 patients Type 33-A3, 7 patients Type 33-B1, 6 patients Type 33-B2, 2 patients Type 33-B3, 5 patients Type 33-C1, 14 patients Type 33-C2 and 7 patients Type 33-C3. Out of 61 patients, 32.8% were OTA type 33-A, 24.6% were OTA type 33-B and 42.6% were OTA type 33-C. There were multiple implants were used to fix the fracture which were locking compression plate (61% of the cases), screw fixation (23%), buttress locking compression plate (5%), buttress plate (7%), external fixator (2%), hybrid external fixator (2%) and supracondylar nail (2%). The mode of fixations was determined by the surgeon preference. The cases were performed by the surgeon (79%) and by medical officer (21%). Lateral incision was commonly made in all types with type 33-A (39.2%), type 33-B (15.7%) and type 33-C (45.1%). Other types of incision includes medial (10%), anterior (5&) and lateral parapatellar approach (2%). Patients were followed up for a mean of 61.95 weeks in distal femur fractures type 33-A, 66.07 weeks in type 33-B fractures and 95.12 weeks in type 33-C fractures (range 8-330 weeks). At final follow-up visit, the mean maximum range of motion was 115 degree in type 33-A fracture, 112 degree in type 33-B fracture and 103.27 degree in type 33-C fracture. There were 2 out of 20 cases of type 33-A distal femur fracture developed complications includes non-union and shortening. Meanwhile, 3 out of 15 cases of type 33-B fractures developed non-union and osteoarthritis. Otherwise, there were 4 out of 26 cases of type 33-C fractures had complications of shortening, surgical site infection and malunion. There were significant association between anatomical radiological outcomes and distal femur fracture. Anatomical score was excellent in 16 patients out of 61 patients with distal femur fractures with type 33-A fracture (N = 8, 50%), type 33-B (N = 4, 25%) and type 33-C fracture (N = 4, 25%). Good anatomical score was 11 in distal femur fracture type 33-A (25%), 11 in type 33-B fracture (25%) and 22 in type 33-C fracture (50%). Unacceptable anatomical radiological score was 1 case in distal femur fracture type 33-A. There was no significant association between Lysholm score with type of distal femur fracture. Distal femur fractures type 33-C score good to excellent higher than type 33-A and type 33-B fractures. There were no statistically significant differences between all sub-types of distal femur fractures in term of quality of life (QOL) SF 36 functional outcomes. The distal femur type 33-B had higher score compare to type 33-A and type 33-C fractures namely physical function, role physical, vitality, mental health and physical health. Conclusion: Based on the results, males formed a majority over females (ratio 4:1) with the predominant age (18 – 40 years). Motor vehicle accidents form the leading causes of distal femur fractures. The functional outcome was affected by type of implant that being used (locking compression plate predominate), surgeon, type of incision (lateral approach predominate), duration of admission, duration of surgery and duration from trauma to definitive treatment. Distal femur fracture type 33-B treated operatively had better functional outcome (Lysholm and Tegner), quality of life (SF-36) and Rassmussen radiological score compare to type 33-A and type 33-C.