Stephen A. Sems

Results of polyaxial locked-plate fixation of periarticular fractures of the knee

BACKGROUND Locked-plate fracture-fixation techniques and designs continue to evolve. Polyaxial locking plates that allow screw angulation and end-point locking have become available; however, there are no clinical data documenting their strength and efficacy, to our knowledge. The purpose of this study was to evaluate the clinical performance of a variable-axis locking plate in a multicenter series of periarticular fractures about the knee. METHODS Between 2003 and 2005, fifty-four patients with a total of fifty-six fractures were treated with a polyaxial locked-plate fixation system (DePuy, Warsaw, Indiana). There were twenty male patients and thirty-four female patients with a mean age of fifty-seven years. There were twenty-five distal femoral fractures and thirty-one proximal tibial fractures. Twelve of the fractures were open. Clinical and radiographic data, including changes in alignment, hardware breakage, or other mechanical complications of the device, were retrospectively reviewed. Function was assessed with use of the Knee Society scores. One patient with a bilateral fracture died less than three months postoperatively, and two patients were lost to follow-up prior to union. Fifty-two fractures in fifty-one patients were followed to union or for a minimum of six months; the mean duration of follow-up was nine months (range, six to twenty-five months). RESULTS Forty-nine (94%) of the fifty-two fractures united. There were no mechanical complications. Most importantly, there was no evidence of varus collapse as a result of polyaxial screw failure. There were three deep infections and one aseptic nonunion. No plate fractured, and no screw cut out. CONCLUSIONS The variable-axis locking plates performed well, with a high rate of fracture union and no evidence of varus collapse due to failure of the polyaxial screw fixation, in a series of complex fractures about the knee. Complication rates were similar to those for historical controls treated with fixed-trajectory locking plates. Polyaxial locking plates offer more fixation versatility without an apparent increase in mechanical complications or loss of reduction.

Acetabular fractures: The role of total hip replacement

Total hip replacement (THR) after acetabular fracture presents unique challenges to the orthopaedic surgeon. The majority of patients can be treated with a standard THR, resulting in a very reasonable outcome. Technical challenges however include infection, residual pelvic deformity, acetabular bone loss with ununited fractures, osteonecrosis of bone fragments, retained metalwork, heterotopic ossification, dealing with the sciatic nerve, and the difficulties of obtaining long-term acetabular component fixation. Indications for an acute THR include young patients with both femoral head and acetabular involvement with severe comminution that cannot be reconstructed, and the elderly, with severe bony comminution. The outcomes of THR for established post-traumatic arthritis include excellent pain relief and functional improvements. The use of modern implants and alternative bearing surfaces should improve outcomes further.

Femoral nerve palsy after pelvic fracture treated with INFIX: a case series.

Objective: The treatment of some pelvic injuries has evolved recently to include the use of a subcutaneous anterior pelvic fixator (INFIX). We present 8 cases of femoral nerve palsy in 6 patients after application of an INFIX to highlight this potentially devastating complication to pelvic surgeons using this technique and discuss how it might be avoided in the future. Design: Retrospective chart review. Case series. Setting: Five level 1 and 2 trauma centers, tertiary referral hospitals. Patients/Participants: Six patients with anterior pelvic ring injury treated with an INFIX who experienced 8 femoral nerve palsies (2 bilateral). Intervention: Removal of internal fixator, treatment for femoral nerve palsy. Main Outcome Measurements: Clinical and electromyographic evaluation of patients. Results: All 6 patients with a total of 8 femoral nerve palsies had their INFIX removed. Variable resolution of the nerve injuries was observed. Conclusions: Application of an INFIX for the treatment of pelvic ring injury carries a potentially devastating risk to the femoral nerve(s). Despite early implant removal after detection of nerve injury, some patients had residual quadriceps weakness, disturbance of the thighs skin sensation, and/or gait disturbance attributable to femoral nerve palsy at the time of early final follow-up. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Total Hip Arthroplasty For Femoral Neck Fracture: Comparing In-Hospital Mortality, Complications, and Disposition to an Elective Patient Population

Patients treated with total hip arthroplasty (THA) for osteoarthritis (OA) and femoral neck fracture (FNF) between 1990-2007 were compared using the National Hospital Discharge Survey (NHDS). In-hospital, post-operative complications and disposition were compared at six-year intervals to establish trends over time. A total of 2,160,061 THAs were performed for OA, while 174,641 were performed for FNF. Peri-operative mortality and pulmonary embolism rates following elective THA were lower at each interval when compared to THA performed for FNF (P<0.001). Hematomas, infections, and dislocations were also higher in the traumatic group. The FNF group showed improvements with respect to mortality and rates of pulmonary embolism, infection, and dislocation over time. During the most recent interval, there was no difference in dislocation rates between the two groups. The length of stay and the percentage of patients discharging to a rehab facility were significantly higher in the FNF group at each time interval.

Incidence of deep venous thrombosis after temporary joint spanning external fixation for complex lower extremity injuries.

OBJECTIVE The purpose of this study was to determine the incidence of deep venous thrombosis (DVT) in a prospective protocol of early spanning external fixation with the concurrent use of low-molecular weight heparin (LMWH) in patients with high-energy lower extremity trauma. SETTING Three level I trauma centers. DESIGN Prospective observational study. PATIENTS One hundred thirty-six consecutive patients with 151 complex lower extremity injuries were treated with a protocol of immediate joint spanning external fixation application and LMWH administration within 24 hours of admission. A total of 143 external fixators were applied. Early patient mobilization was encouraged and possible due to the skeletal stability provided by the external fixator. There were 87 men and 49 women with a mean age of 43 years. There were 62 proximal tibia fractures (Orthopaedic Trauma Association [OTA] Fracture Classification 41), 4 tibial shaft fractures (OTA 42), 49 distal tibia-fibula fractures (OTA 43, 44), 14 femur fractures (OTA 32, 33), 8 calcaneus fractures (OTA 73), 10 knee dislocations, and 4 talus fracture dislocations. Forty-eight injuries (32%) were open. INTERVENTION Temporary joint spanning external fixator placement, LMWH administration, and early mobilization within 24 hours of admission. Duplex ultrasonography of the bilateral lower extremities within 1 day to 3 days before fixator removal and definitive fixation procedure. MAIN OUTCOME MEASUREMENTS Presence of DVT on duplex ultrasound examination. RESULTS Duplex ultrasonography was negative for DVT in all but three patients for an incidence of 2.1% (3 of 143 fixators). There were no bleeding complications secondary to the use of LMWH while the temporary external fixator was in place. CONCLUSION The incidence of DVT in patients treated with a protocol of early joint spanning external fixation and LMWH administration does not exceed historical controls. The early restoration of limb length, alignment, and stability allows early mobilization, which may contribute to the prevention of DVT.

Safety of Clopidogrel in Hip Fracture Surgery

OBJECTIVE To compare postoperative outcomes of hip fracture surgery in patients who were and were not taking clopidogrel at the time of surgery. PATIENTS AND METHODS Using the Rochester Epidemiology Project database, we performed a population-based, retrospective cohort study comparing patients who were and were not taking clopidogrel at the time of hip fracture surgery between January 1, 1996, and June 30, 2010. Primary outcomes were perioperative bleeding and mortality. Secondary outcomes were perioperative thrombotic events. RESULTS During the study period, 40 residents of Olmsted County, Minnesota (median age, 83 years), who were taking clopidogrel underwent hip fracture repair. These 40 patients were matched 2:1 with 80 control patients (median age, 84 years). The groups were similar in age, sex, American Society of Anesthesiologists score, type of surgical procedure, and use of deep venous thrombosis prophylaxis. The mean time from admission to surgery was less than 36 hours for each cohort. Perioperative bleeding complications and mortality were not significantly different between patients who were and were not taking clopidogrel at the time of hip fracture surgery. Combined bleeding outcome criteria was met in 48% of the clopidogrel cohort and 45% of the control cohort (relative risk, 1.06; 95% CI, 0.70-1.58; P=.80). One-year mortality was 28% in the clopidogrel cohort and 29% in the control cohort (hazard ratio, 1.33; 95% CI, 0.84-2.12; P=.23). CONCLUSION Although the small sample size precludes making a definitive conclusion, we found no evidence that prompt surgical treatment of hip fracture in patients taking clopidogrel compromises perioperative outcomes.

Results of Polyaxial Locked-Plate Fixation of Periarticular Fractures of the Knee: Surgical Technique

BACKGROUND Locked-plate fracture-fixation techniques and designs continue to evolve. Polyaxial locking plates that allow screw angulation and end-point locking have become available; however, there are no clinical data documenting their strength and efficacy, to our knowledge. The purpose of this study was to evaluate the clinical performance of a variable-axis locking plate in a multicenter series of periarticular fractures about the knee. METHODS Between 2003 and 2005, fifty-four patients with a total of fifty-six fractures were treated with a polyaxial locked-plate fixation system (DePuy, Warsaw, Indiana). There were twenty male patients and thirty-four female patients with a mean age of fifty-seven years. There were twenty-five distal femoral fractures and thirty-one proximal tibial fractures. Twelve of the fractures were open. Clinical and radiographic data, including changes in alignment, hardware breakage, or other mechanical complications of the device, were retrospectively reviewed. Function was assessed with use of the Knee Society scores. One patient with a bilateral fracture died less than three months postoperatively, and two patients were lost to follow-up prior to union. Fifty-two fractures in fifty-one patients were followed to union or for a minimum of six months; the mean duration of follow-up was nine months (range, six to twenty-five months). RESULTS Forty-nine (94%) of the fifty-two fractures united. There were no mechanical complications. Most importantly, there was no evidence of varus collapse as a result of polyaxial screw failure. There were three deep infections and one aseptic nonunion. No plate fractured, and no screw cut out. CONCLUSIONS The variable-axis locking plates performed well, with a high rate of fracture union and no evidence of varus collapse due to failure of the polyaxial screw fixation, in a series of complex fractures about the knee. Complication rates were similar to those for historical controls treated with fixed-trajectory locking plates. Polyaxial locking plates offer more fixation versatility without an apparent increase in mechanical complications or loss of reduction.

Posttraumatic Total Knee Arthroplasty Continues to Have Worse Outcome Than Total Knee Arthroplasty for Osteoarthritis

Small studies have shown that patients who undergo TKA following a distal femur and/or tibial plateau fracture have inferior results. The purpose of this study was to evaluate the mid-term outcomes of a large group of patients undergoing TKA following periarticular knee fractures. We identified 531 patients who underwent a TKA following a periarticular fracture from 1990 to 2012; comparing outcomes to 19,641 patients undergoing primary TKA for osteoarthritis. Periarticular fracture significantly increased the risk of revision TKA, infection and complications. There was no difference in the need for revision TKA or infection based on fracture location. Patients with TKA following a periarticular fracture have worse overall revision free survival compared to with OA, with 1 in 4 patients requiring revision TKA by 15 years.

Arthrofibrosis After Periarticular Fracture Fixation

Arthrofibrosis after periarticular fractures can create clinically significant impairments in both the upper and lower extremities. The shoulder, elbow, and knee are particularly susceptible to the condition. Many risk factors for the development of arthrofibrosis cannot be controlled by the patient or surgeon. Early postoperative motion should be promoted whenever possible. Manipulations under anesthesia are effective for a period of time in certain fracture patterns, and open or arthroscopic surgical debridements should be reserved for the patient for whom nonoperative modalities fail and who has a clinically significant deficit.

Patella Fractures Prior to Total Knee Arthroplasty: Worse Outcomes but Equivalent Survivorship

Distal femur and/or tibial plateau fractures adversely affect outcomes of TKA; however it is unknown if a previous patella fracture affects outcome. We reviewed 113 patients undergoing TKA with a previous patella fracture from 1990 to 2012. Component survival was compared to 19,641 patients undergoing TKA for osteoarthritis during the same period. The 15-year implant survivals following a previous patella fracture was 86%. There was no difference in implant survival compared to patients undergoing TKA for OA (P=0.31). Knee society scores significantly improved following TKA; however patients with a fracture had complications related to knee flexion. Patients undergoing primary TKA following a patella fracture have similar overall revision free survival compared to those undergoing TKA for OA at 15-years.