OBJECTIVE Floating knee injuries are complex injuries and are usually caused by
highvelocity trauma. These injuries are often associated with life treating
injuries, which should take precedent over extremity injuries. The authors
reviewed the outcomes of floating knee injuries managed in this institute
from 2003 to 2015.
METHOD A retrospective study was conducted of all patients with floating knee injuries from 2003 to 2015. Twelve patients were included in the study. Data related to fracture type, associated injuries, treatmentmodalities, and complications were noted. Functional assessment was performed using themodified Karlstromand Olerud criteria after complete bony union.
RESULT The mechanism of injury was motor vehicle accident in all patients. The mean follow up was four years. The mean age of patients was 34.75 year. The mean union time was 6.5 months in femurs and 6.7 month in tibias. The complications were knee stiffness, delayed union, and infection. According to modified Karlstrom criteria, there were three - excellent, five - good, three - fair, and one poor result.
CONCLUSION Floating knee injuries are severe injuries and are usually associated with multi-organ injuries. Early detection and appropriate management of associated injuries, early fixation of fractures, and postoperative rehabilitation are needed for good outcome. Complications are frequent, in the form of delayed union, knee stiffness, and infection.
Keywords: femoral fractures; tibial fractures; knee injuries; fracture fixation.
OBJETIVO As lesões do tipo joelho flutuante (FKIs, na sigla em inglês) são complexas e
são geralmente causadas por trauma de alta velocidade. Estas lesões são
frequentemente associadas a lesões que causamrisco demorte, que devemter
precedente sobre lesões nas extremidades. Os autores revisaram os resultados
das lesões do tipo joelho flutuante tratadas nesta instituição entre 2003 e
MÉTODO Foi realizado um estudo retrospectivo de todos os pacientes com FKIs de 2003 a 2015. Doze pacientes foram incluídos no estudo. Os dados relacionados ao tipo de fratura, lesões associadas, modalidades de tratamento e complicações foram observados. A avaliação funcional foi realizada utilizando os critérios de Karlstrom modificados após a união óssea completa.
RESULTADOS Omecanismo de lesão foi acidente automobilístico em todos os pacientes. O acompanhamento médio foi de 4 anos. A média de idade dos pacientes foi de 34,75 anos. O tempo médio de união óssea foi de 6,5 meses nos fêmures e de 6,7 meses nas tíbias. As complicações foram rigidez do joelho, união óssea tardia e infecção. De acordo com os critérios modificados de Karlstrom, três resultados foram considerados excelentes, cinco bons, três razoáveis e um resultado foi considerado ruim.
CONCLUSÃO Lesões do tipo joelho flutuante são graves e são geralmente associadas a lesões de vários órgãos. A detecção precoce e o tratamento adequado das lesões associadas, a afixação precoce das fraturas e a reabilitação pós-operatória são necessários para um bom resultado. As complicações são frequentes, sob a forma de união óssea tardia, rigidez do joelho e infecção.
Palavras-chave: fraturas femorais; fraturas tibiais; lesões no joelho; fixação de fratura.
|Citation: Yadav V, Suri HS, Vijayvargiya M, Agashe V, Shetty V. “Floating knee,” an Uncommon Injury: Analysis of 12 Cases*. 54(1):53. doi:10.1016/j.rboe.2017.09.007|
Study conducted at Department of Orthopedics, P.D. Hinduja National Hospital,
Mumbai, India. Published originally by Elsevier Editora Ltda. © 2018
Sociedade Brasileira de Ortopedia e Traumatologia.
Vivek Shetty's ORCID is https://orcid.org/0000-0002-0237-7309.
|Received: Julho 24 2017; Accepted: Setembro 05 2017|
Floating knee injuries (FKI) are deﬁned as ipsilateral fractures of tibia and femur, which could include diaphysis, metaphysisor intra articular fractures.1 These fractures range from simple diaphyseal to complex articular type. The term ﬂoating knee was described by Blake and Mcbride and Blake in 1975.2
Although exact incidence of a FKI is not known, they are relatively uncommon. These injuries are usually followed by high velocity trauma, most often motor vehicle collision, commonly associated with extensive soft tissue injuries and life-threatening injuries. Kao et al. in their series of 419 patients reported 110 (26%) head injury, 37 (8%) pelvic injury, 29 (7%)chest injury and 230 (55%) contralateral extremity injury.3 Incidence of vascular injury associated with FKI range from7% to 29%.4,5 Excessive blood loss, fat embolism, delayed or nonunion, joint stiffness, delayed mobilization, amputation and infection are some other complications reported in FKI.3
With advancement of fracture ﬁxation methods and operative technique management of FKI has improved over decades. This can be attributed to management of polytrauma patients following basic principles of ATLS.
This retrospective study was performed to assess outcome for treatment of FKI, associated injuries and complications thereafter.
MATERIAL AND METHODS
From 2004 to 2015, 12 patients with FKI were admitted in emergency at our tertiary care institute. All patients who sustained FKI with age between 18 and 65 year either open or closed were included in study. As most of the patients with FKI were victims of polytrauma, initial management was performed with resuscitation and hemodynamic stabilization of patient and splinting of affected limb as per ATLS protocol. All twelve patients required resuscitation at emergency department, of these two patients required endotracheal intubation and intensive care.
Patients with head injury, chest injury and pelvic injuries were managed accordingly before surgical stabilization of fracture. One patient had large hematoma in pelvis due to pelvic fracture (Tile type B2.2), causing fall in hemoglobin level despite blood transfusion, requiring embolization of sacral and obturator artery.
Fraser classiﬁcation was used to classify FKI.5 Open fracture were classiﬁed according to Gustilo and Anderson’s classiﬁcation.6 Surgical management was done once patients were hemodynamically stable. Femur fracture was ﬁxed ﬁrst followed by tibia fracture. Intra medullary nail was used for diaphyseal fractures and plate was used for metaphyseal and intra-articular fractures (►Figs. 1 and 2). If open wounds were present it was debrided and assessed accordingly for delayed primary closure, skin graft or ﬂap.
During perioperative period all patients received three doses of antibiotic (Cefzolin). Thromboprophylaxis was started in all patients in postoperative period. If patient condition permitted, active and passive knee exercise was initiated day one post-surgery. Weight bearing walking with walker was guided by mode of ﬁxation used.
On going through hospital records, patients were seen at regular follow up at 1, 3, 6, 12 months and yearly. On each follow up clinical and radiological assessment was done. Radiological assessment was done by X-ray to assess bony union. Functional assessment was done using modiﬁed Karlstrom’s criteria after bony union was conﬁrmed.7,8
Mean age of patients were 34.75 years (range 19-54). The mean duration of follow up was 4 years (range 1-11 year). The mean duration of complete union was 6.5 month in femur and 6.7 month in tibia. All twelve patients were involved in road trafﬁc accident. The right side was involved in seven patients and left side in ﬁve patients. There were 5 type-1, 2 type-2a, 2 type-2b and 3 type-2c FKI according to Fraser classiﬁcation (►Table 1). There were nine (75%) open FKI, in which nine were femur (3 grade 2, 3 grade 3a, 3 grade 3b) and ﬁve were tibia (4 grade 3a, 1 grade 3b) (►Table 2). Four patients had chest injury and two patients needed intercostal chest drain for hemothorax. Three patients had pelvic injury and two patients required internal ﬁxation (one Tile B1 and Tile B2.2) and one patient (Tile A2) treated conservatively. None of the patients had head injury, however two patients had periorbital ecchymosis for which CT scan of brain was advised to rule out any intracranial bleed or skull fracture. Eight patients had other associated extremities injury (►Table 3). None of the patients had neurovascular injury in extremities.
|Mean age||34.75 year (19-54)|
|Close fracture||3 (25%)|
|Open fracture||9 (75%)|
|Type of fracture (according to Fraser classification)|
|Type 1-Extra articular fracture of femur and tibia||5 (41.66%)|
|Type 2a - Extra articular femur and intraarticular tibia fracture||2 (16.66%)|
|Type 2b - Extraarticular tibiaand intra articular femur fracture||2 (16.66%)|
|Type 2c - Intra articular femur and tibia fracture||3 (25.00%)|
|IMN in tibia||4(36%)|
|Plate in tibia||5 (45%)|
|Fixator in tibia||2 (18.18%)|
|IMN in femur||5(45%)|
|Plate in femur||6(54%)|
|Fixator in femur||1(8.3%)|
|Mean duration of union in months|
|Mean time from injury to surgical interval||4.8 days (1-30)|
|Chest injury (hemothorax, pneumohemothorax, rib fracture)||4 (33.33%)|
|Resuscitation required in patients||4 (33.33%)|
|ICU stay required in patients||7 (58.33%)|
|Blood transfusion required in patients||7 (58.33%)|
|Mean duration of stay in hospital||22.4 days (8-36)|
|Other extremity injury in patients||8 (66%)|
|Grade 2||3 (33.3%)||0|
|Grade 3a||3 (33.3%)||4 (44.4%)|
|Grade 3b||3 (33.3%)||1 (11.1%)|
|Ipsilateral fracture neck of femur||2|
|Distal end radius||2|
|Contralateral shaft femur fracture||1|
|Anterior cruciate ligament injury||1|
The complications encountered were knee stiffness in ﬁve patients for which manipulation under anesthesia were done for all at 3 months after surgery. Delayed union was noted in four tibiae and four femur fractures. One femur and one tibia fracture required dynamization after three months of surgery and went on to unite at 8 month and 6 month respectively. Remaining three femur fractures where plate, nail and external ﬁxator was used, were further observed without any intervention till union at average of 11 month. Similarly remaining three tibia fractures where plate, nail and POP cast was used, were further observed without intervention till union at average of 9.20 month. Five patients developed early superﬁcial infection over surgical site in tibia which was resolved with antibiotics. One patient had delayed infection after three year of surgery in tibia which settled with debridement and implant removal (►Table 4).
|Delayed union femur||4 (33%)|
|Delayed union tibia||4 (33%)|
|Early infection||5 (41%)|
|Delayed infection||1 (0.8%)|
|Knee stiffness||5 (41%)|
Three patients had wound defect over leg which were managed with split skin graft in one patient and ﬂap (gastrocnemius ﬂap, local advancement ﬂap) coverage in two patients. One patient had wound defect over thigh which was closed with secondary suturing. Functional assessment was done using modiﬁed Karlstrom criteria after complete bony union which were excellent in 3, good in 5, fair in 3 and 1 poor result (►Table 5 and ►Fig. 3).
FKI are uncommon injuries and its true incidence remains unknown. Patients with FKI are usually victim of high velocity trauma, mostly motor vehicle accident. It is not just extremity injuries, several organ injuries and multiple fractures are often associated, which can be life threatening. We found 66% patients had associated injury in our study, which is comparable with other studies.7,9 Careful evaluation of patient was carried out to identify other associated injuries and treatment priority was given to life threatening injury over extremity injury.
The role of early total care (ETC) and damage control orthopedic (DCO) in polytrauma has been always a controversial issue. In stable patients, ETC is more appropriate and in unstable patients DCO is required. However, considerable doubt remains in borderline patients. Some author advised ETC in all patients except in more critical patients and some advised DCO and delayed skeleton stabilization.10,11 The literature has also reports utility of serum lactate level to assess timing of treatment and mortality, but its role is still controversial to predict survival after major injury.12,13 In our study we did not measure serum lactate level. In conclusion, management for polytrauma patients should be individualized after assessing the beneﬁt of early deﬁnitive fracture ﬁxation versus potential life-threatening risk of systemic complications such as fat embolism, acute lung injury or multiple organ failure.14
Various studies showed good result after operative treatment of FKI.8,15-18 There is common agreement on recent studies that best management for FKI is surgical ﬁxation of both the fracture with intramedullary nail whenever possible.19-21 Rethnam et al. treated FKI injuries with intramedullary nail for most of extraarticular fracture and plate for most of intraarticular fracture, and found the fracture union time and functional recovery was better in those patient which were treated with intramedullary nail.19 Theodoratus et al.20 in their study recommended intramedullary nail as method of choice for treatment of ipsilateral diaphyseal tibia and femur fracture except open grade 3b and c fracture. Dwyer et al.21 compare four treatment modalities to ﬁxFKI and concluded that excellent to good result were obtained when shaft femur and tibia fracture were treated with intramedullary nail or combined modality (intramedullary nail for femur fracture and cast brace for tibia fracture), and poor result when both fracture treated with external ﬁxator. The incidence of amputation was reported up to 27% in FKI which had massive soft tissue crushing, severe infection and neurovascular injuries.21 In our study one patient underwent above knee amputation due to severe local infection and septicemia despite of multiple debridement surgeries.
In our study we used intramedullary nail in ﬁve shaft femur fracture and in four shaft tibia fracture. We used locking plate in ﬁve tibia fracture (articular and metaphyseal) and six femur fractures (articular and metaphyseal). In one patient a cast brace was used to treat grade 3a open shaft tibia fracture (►Table 1). External ﬁxator was used as a deﬁnitive ﬁxation in two tibiae and one femur fracture. The mean time of bony union were 6.5 month in femur and 6.7 month in tibia which were little higher from other published study.19
In literature we found that outcome of FKI was often variable, some author reported 0 excellent result and other author reported excellent result up to 53% (►Table 6). These variable results might be due to associated neurovascular injury, open fracture and variable fracture pattern with FKI.3,7,19,22-24 In our study, we found excellent result in three (25%) patients, good result in ﬁve (41%) patients, fair in three (25%) patients, poor result in one (9%) patient according to modiﬁed Karlstrom criteria which were comparable to other study group (►Table 5).
|Studies||Open fracture||Vascular injury||Nerve injury||Infection||Functional outcome|
|Ostrum et al., 200023||41%||5%||NA||NA||Excellent or good - 88% Fair - 6% Poor - 6%|
|Ríos et al., 200322||57%||5%||5%||19%||Excellent - 10% Good - 34%Fair - 38%Poor - 19%|
|Rethnam et al., 200719||20%||3%||3%||7%||Excellent - 51% Good - 31% Fair - 7% Poor -10%|
|Oñorbe et al., 20087||47%||13%||27%||13%||Excellent - 0 Good - 33% Fair - 27% Poor - 40%|
|Kao et al., 20103||63%||NA||NA||21%||NA|
|Hegazy et al., 201124||13%||NA||NA||7%||Excellent - 53% Good - 26% Fair - 13% Poor - 7%|
|Our study||75%||0||0||26%||Excellent - 25% Good - 41% Fair - 25% Poor - 9%|
FKI are usually associated with high velocity trauma which can cause severe soft tissue injury, with high incidence of open fractures reported up to 77%.4,15 Incidence of infection were reported up to 21% in these injuries (3). In our series we found infection rate up to 26%, this high incidence may be attribute to high incidence (75%) of open fractures.
Vascular insult associated with FKI have been reported in the literature from 7% to 29%.4,5 Neurological lesion also have been reported with FKI. Rios et al.22 and Onorbe et al.7 reported neurological injury associated with FKI were 5% and 27% in their study respectively. In our series no patient had any vascular and neurological injuries in any patients (►Table 6).
Retrospective study and small sample size, especially in all three types of fractures to assess comparable outcome are limitations of our study.
In summary, FKI is severe injury which is usually associated with other life-threatening injury which should be identiﬁed carefully and managed on priority basis. FKI usually require multidisciplinary management with critical care backup. Treatment of these injuries should be individualized on basis of patient hemodynamic condition, fracture pattern and associated soft tissue injury. In general, intramedullary nails are best for diaphyseal fractures and plate osteosynthesis for intra articular and metaphyseal fractures. The complications are remaining high in our study in form of delayed union, knee stiffness and infection.
We are thankful to the residents and colleagues at Department of Orthopedics P.D. Hinduja National Hospital and Research Center Mumbai for helping in this study. No beneﬁts or funds were received in support of this study.