Outcome of Bone Transport Using Ilizarov External Fixator in Infected Non-union of Tibia with Large Bone Defects: Comparison of Those with 5-10 cm Bone Defect with Those Having ≥ 11 cm Bone Defect.

Background: Ilizarov external fixation has become the treatment of choice for infected non-union of tibia. Varying degrees of bone loss and different strategies of treatment in the published reports make comparing outcomes difficult. This study hopes to bridge this gap in the literature by focussing exclusively on bone transport in patients with bone loss of 5 cm or more. Methodology: This is a prospective case series conducted at a tertiary level orthopaedic speciality hospital. Outcomes are measured by Association of the Study and Application of Method of Ilizarov (ASAMI) bony scores, ASAMI functional scores, Lengthening Index and by assessing complications encountered. Results: There were 49 patients in this study with an average of 9.57 cm bone gap. Among these, 29 patients had a bone gap of 5-10 cm and 20 patients had a bone gap of ≥ 11 cm. According to the ASAMI bony score, 42 patients had excellent or good outcomes with two fair results and five poor results. The ASAMI functional scores were 45 excellent to good outcomes, four fair and no poor results or failures. Fixed flexion deformity of the knee of more than 5°, ankle stiffness and soft tissue interposition were significantly more frequent in those with bone gap of ≥ 11 cm. Trifocal transport and bone grafting at docking significantly improved the lengthening index. Conclusion: Even massive bone defects of 11 cm or more can be reliably healed by bone transport using Ilizarov external fixation, but with a significantly higher rate of complications. Level of evidence: Level IV.

High Recurrence Rates of Hyperextension After Total Knee Arthroplasty in Asian Patients With Preoperative Knee Hyperextension: A Prospective Observational Study.

INTRODUCTION: Genu recurvatum is a well-known problem in total knee arthroplasty (TKA) in patients with and without neuromuscular disorders. Hyperextension of the knee joint does not reoccur significantly following adequate correction during TKA is the generally accepted notion. The literature regarding the reoccurrence of genu recurvatum in patients after TKA with preoperative genu recurvatum is scarce. The current study is an intermediate-range follow-up study to assess the pre- and postoperative sagittal plane profiles of Asian patients with genu recurvatum who underwent TKA. Changes in the sagittal profile in the immediate postoperative period were compared with the sagittal plane profile during the follow-up to the time of the final follow-up. MATERIALS AND METHODS: This study was a prospective observational study of 21 patients (35 knees) with preoperative hyperextension of the affected knee who underwent total knee arthroplasty between July 2014 and September 2018, in our centre. The inclusion criteria were patients with primary osteoarthritis of the knee with recurvatum deformity ≥5° as measured preoperatively on a standing lateral radiograph. The exclusion criteria were neuropathic joints, post-traumatic arthritis, inflammatory arthritis, arthritis-associated neuromuscular disorders and revision procedures. The preoperative patients were divided into two groups: those with hyperextension of ≤10° and those with hyperextension of >10°. Radiographic measurements were done using the DICOM software (Kriens, Switzerland). The mean follow-up was 4.7 years (range: 3.6 to 7.6 years), and the minimum follow-up period was 3.6 years. No patients were lost to follow-up. All patients were evaluated clinically pre- and postoperatively using the Knee Society score. The knee range of movement and the coronal and sagittal profiles were recorded using standing radiographs. Statistical evaluation was done using the Chi-square test and the Wilcoxon signed-rank tests (SPSS version 17, Chicago, IL SPSS Inc, 2008). RESULTS: Twenty-one patients (35 knees) with preoperative knee hyperextension underwent total knee arthroplasty with the mean age of patients being 59.38 years and the mean BMI of 32.28. The mean preoperative hyperextension was -10.1° (range: -5° to -26°). Early postoperative sagittal alignment (mean) was +4.5° (3° to 10°), and the mean sagittal alignment at final follow-up was -10.9° (-5° to -15°) (positive values indicate residual knee flexion, and negative values indicate hyperextension). There was no significant difference in the preoperative sagittal profiles of patients with BMI <30 and ≥30 (p=0.43). There was no statistically significant difference (p=0.19) between those with hyperextension of ≤10° and those with hyperextension of >10°. CONCLUSION:  Till now, none of the patients have complained of symptoms related to hyperextension, although the rate of recurrence of hyperextension is high. Long-term follow-up is essential in patients with recurvatum deformity who have undergone TKA since delayed recurrence of hyperextension is possible despite adequate intraoperative correction of the deformity. Accurate preoperative prediction about the magnitude of postoperative deformity is not feasible. It is essential to counsel patients preoperatively that hyperextension may recur even after exercising sufficient care in the operative procedure to minimize its occurrence.

Vascularized Ulnar Transposition and Ulno-scapholunate Fusion for Reconstructing Campanacci Grade 3 Giant Cell Tumor of Distal Radius: Technique and a Series of 5 Cases.

Campanacci grade 3 distal radius giant cell tumors are difficult to treat and just doing a curettage and bone grafting is insufficient. These lesions are associated with a high chance of recurrence. We are presenting our technique and series of 5 patients who underwent enbloc excision and ulna transposition with ulno-scapholunate fusion. Between 2014 and 2017 5 patients underwent en bloc excision of Campanacci grade 3 giant cell tumor of the distal radius, ulna transposition and ulno carpal fusion. These patients were regularly followed for evidence of union, range of motion, grip strength, and to look for recurrence of tumor. All 5 patients were Campanacci grade 3 tumors. The average duration of symptoms was 5 months (1 to 9 mo). The average duration of follow-up was 33 months (24 to 48 mo). The average time for ulno-scapholuante fusion was 8 weeks (6 to 10 wk) and the average time to radio ulnar fusion was 14.5 weeks (12 to 16 wk). The average arc of wrist flexion and extension was 34 degrees. The average grip strength was 58.2% of the contralateral side (48% to 69%). In conclusion vascularized ulnar transposition with partial wrist fusion for a Camapanacci grade 3 giant cell tumor is an alternate procedure in the management of these difficult tumors.

Revision Anterior Cruciate Ligament Reconstruction in the Nonathlete Population.

BACKGROUND: There is considerable literature about revision anterior cruciate ligament (ACL) reconstruction in athletes vut there is little published evidence about the same in the nonathletes. The injury itself may remain underdiagnosed and untreated in nonsports persons. This study highlights the high incidence of ACL injury in the nonathletic patient cohort, revision rates, and the outcomes of revision ACL reconstruction. MATERIALS AND METHODS: 856 nonathletic patients who underwent primary ACL reconstruction were included in this retrospective study. Patients were asked on phone whether they had undergone revision surgery and whether they had symptoms severe enough to seek reintervention. Clinical assessment and preoperative and postoperative International Knee Documentation Committee (IKDC) and Lysholm scoring were used to followup patients who underwent revision intervention. RESULTS: Clinically, symptomatic revision rate was 5.9% (51 out of 856 patients), and 33 out of these 856 patients (3.9%) underwent revision ACL reconstruction. The reasons for revision were rupture of the previous graft in 21 and laxity (incompetence) of the graft in 12 patients. The mean preoperative and postoperative IKDC scores were 44.1 and 69.8, respectively, and the improvement was statistically significant (P < 0.001). The IKDC score following revision ACL reconstruction was significantly better in those patients who underwent revision <1 year following the onset of recurrent symptoms (P = 0.015). Meniscal tears were present in 47.6%, and chondral injuries were seen in 33.3% of patients. The tibial tunnel positioning was abnormal in 70% of patients. Femoral tunnel positioning was aberrant in all the patients. CONCLUSIONS: The revision rate of primary ACL reconstruction of 5.9% in nonathletes and revision ACL reconstruction rate of 3.9% are similar to the reported revision rates of 2.9%-5.8% in athletic patients. Similar to athletes, suboptimal tunnel placement is the major contributor to failure in nonathletes also.

Prognostic potential of markers of bone turnover in delayed-healing tibial diaphyseal fractures.

INTRODUCTION: Clinical and radiographic examinations detect delayed or nonunion only after the event has occurred. Biochemical markers of bone turnover (BTMs) are promising laboratory tools that offer an early insight into the likelihood of delayed union. We hypothesized that BTMs display temporal variations following fractures and the behavior of BTMs differ between normal and delayed union of fractures. METHODS: This was a prospective study of patients with closed fracture of tibia treated with intramedullary, interlocking nailing. BTM assays (NTX, BSAP, P1NP and osteocalcin) and clinical and radiographic assessments were obtained preoperatively and postoperatively at 8,12, 24, 36 and 72 weeks. Temporal trend of elevation of serum levels of BTMs post-fracture was the primary assessment criterion and radiographic and clinical assessment of fracture union were the secondary assessment criteria. RESULTS: The average time for fracture union was 15.24 weeks (range 15-19 weeks). The values of both bone formation and resorption markers peaked at the eighth week following the fracture. Resorption markers returned to baseline by 36 weeks. Among the formation markers, BSAP levels showed the smallest increase and returned to baseline earlier (36 weeks) than P1NP and osteocalcin (72 weeks). P1NP showed the most dramatic change, increasing to 2.5 times the mean baseline level at 8 weeks in normal union of fractures. The levels of bone formation markers (BSAP, OC, PINP) were significantly lower in patients with delayed union. There was no significant difference in the levels of the resorption marker (NTX) between normal and delayed union patients. CONCLUSION: Serial monitoring of biochemical markers of bone turnover can be used as an adjunct to clinical and radiological observations to predict delayed union LEVEL OF EVIDENCE: Level 2 (prospective observational study).

Lateralization of Tibial Plateau Reference Point Improves Accuracy of Tibial Resection in Total Knee Arthroplasty in Patients with Proximal Tibia Vara.

BACKGROUND: The tibial cut referenced to the center of the intercondylar eminence often leads to varus malalignment in the presence of preexisting proximal tibia vara. The purpose of this study was to investigate the effect of lateralization of the lateral tibial plateau reference point (based on the amount of proximal tibia vara) on the postoperative coronal plane alignment. METHODS: In this prospective cohort study, 62 patients (95 knees) with osteoarthritis and proximal tibia vara underwent primary total knee arthroplasty using a lateral tibial plateau reference point for the extramedullary jig. The pre- and postoperative radiographs were obtained for measurement of mechanical axis deviation, degree of tibia vara, proximal lateral reference point of the tibial condyle, and coronal alignment of the femoral and tibial components. The distance between the tibial reference point and the center of the intercondylar eminence was measured intraoperatively. RESULTS: The mean tibia vara was 7.1° (standard deviation [SD], 2.3°). The mean lateral displacement of the reference point was 7 mm (SD, 2.2 mm). Postoperative tibiofemoral angle was 6° to 10° of valgus in 94% of cases. There was a strong correlation between the magnitude of tibia vara and the amount of lateralization of the tibial reference point (R2 = 0.79, p < 0.001). CONCLUSIONS: In total knee arthroplasty patients with proximal tibia vara, reasonable accuracy can be achieved with use of the extramedullary jig for tibial component alignment by lateralizing the proximal tibial reference point.

Adjacent Disc Stress Following Floating Lumbar Spine Fusion: A Finite Element Study.

STUDY DESIGN: Experimental study. PURPOSE: The study aimed to develop a finite element (FE) model to determine the stress on the discs adjacent to the fused segment following different types of floating lumbar spinal fusions. OVERVIEW OF LITERATURE: The quantification of the adjacent disc stress following different types of floating lumbar fusions has not been reported. The magnitude of the stress on the discs above and below the floating fusion remains unknown. METHODS: A computer-aided engineering-based approach using implicit FE analysis was employed to assess the stress on the lumbar discs above and below the floating fusion segment (L4-L5) following anterior and posterior lumbar spine fusions at one, two, and three levels (with and without instrumentation). RESULTS: Both discs suprajacent and infrajacent to the floating fusion experienced increased stress, but the suprajacent disc experienced relatively high stress level. Instrumentation increased the stress on the discs suprajacent and infrajacent to the floating fusion, but the magnitude of stress on the suprajacent disc remained relatively high. CONCLUSIONS: The FE model was employed under similar loading and boundary conditions to provide quantitative data, which will be useful for clinicians to understand the probable long-term effects of floating fusions.

Choice of surgical approach for capitellar fractures based on pathoanatomy of fractures: outcomes of surgical management.

The understanding of the anatomic configuration of the fractures of the capitellum has enhanced in the last few years, and the classification of these fractures continues to evolve. It is essential to tailor the surgical approaches to these fractures based on the state-of-the-art classifications. Thirty-three patients with fractures of the capitellum were included in this retrospective study. The mean age of the patients was 37.9 years, and the mean follow-up period was 24.6 months. Seventeen patients had Bryan-Morrey type I fracture, three had type II fracture, two had type III fracture and eleven had type IV fracture. Of the 11 patients with Bryan-Morrey type 4 fracture, 5 patients belonged to Dubberley 2A and 3A category and 6 patients belonged to Dubberley 2B and 3B category. Bryan-Morrey type 1, 2 and 3 fractures were approached via extended lateral approach. Bryan-Morrey type 4 was further classified using the Dubberley classification. Dubberley 2A and 3A fractures were approached via the anterolateral approach, and Dubberley 2B and 3B fractures were approached via the posterior transolecranon approach. Fracture united in all patients. Three patients showed slight delay in union, but union was achieved eventually. Two patients had avascular necrosis of the capitellar fragment. The mean range of flexion/extension was 133° (SD ± 8.0°), and pronation/supination was 151° (SD ± 6.7°). The mean Mayo Elbow Performance Index at final follow-up was 80.9 (SD ± 13.9). Based on the MEPI score, 14 patients had excellent, 10 patients had good, 6 patients had fair and 3 patients had poor results (Dubberley type 3B fractures). Correct choice of surgical approach facilitates the accuracy of reduction and fixation of these difficult fractures. It also helps to minimize the requirement of two-incision approach. Anterolateral approach is an excellent approach for Dubberley 2A and 3A fractures. LEVEL OF EVIDENCE: Level IV.

Lateralization of Femoral Entry Point to Improve the Coronal Alignment During Total Knee Arthroplasty in Patients With Bowed Femur.

BACKGROUND: Intramedullary jigs are most often used for distal femoral bone cuts in total knee arthroplasty (TKA). However, the accuracy of bone cuts in the distal femur may be affected by the presence of diaphyseal deformities of the femur. METHODS: Sixty-three patients (88 knees) with lateral bowing of the femur underwent primary TKA using a lateralized femoral entry point for intramedullary femoral guide. The following measurements were obtained on the preoperative and postoperative scanograms-mechanical axis deviation, degree of femoral bowing, femoral entry point from the intercondylar sulcus, distance from the center of the knee to the mechanical axis, and coronal alignment of femoral and tibial components. RESULTS: In 48.8% of cases, the femoral entry point was 3-5 mm lateral to the intercondylar notch, in 44.4% of cases, it was 6-10 mm lateral to the notch, and in 6.8% of cases, it was 10-15 mm lateral to the intercondylar notch. Postoperatively the tibiofemoral angle was 6-10 degrees of valgus in 96% of cases. The postoperative mechanical axis was within 3 mm from the center of the knee in 80 of the 88 knees (90.9%). For every 1° increase in femoral bowing, the entry point was lateralized by an average of 1.04 mm. CONCLUSION: The location of femoral entry point is important in TKA in patients with coronal plane deformity of the femur. In patients with lateral femoral bowing of 5° or more, a lateralized femoral entry point is useful in allowing straighter passage of long intramedullary femoral rod and this resulted in good mechanical axis alignment and femorotibial component alignment in over 90% of patients in our series.

Long-Term Effects of Segmental Lumbar Spinal Fusion on Adjacent Healthy Discs: A Finite Element Study.

STUDY DESIGN: Experimental study. PURPOSE: The aim of the study was to develop a finite element (FE) model to study the long-term effects of various types of lumbar spinal interventions on the discs adjacent to the fused segment. OVERVIEW OF LITERATURE: Earlier FE studies have been limited to one particular type of fusion and comparative quantification of the adjacent disc stresses for different types of surgical interventions has not been reported. METHODS: A computer aided engineering (CAE) based approach using implicit FE analysis assessed the stresses in the lumbar discs adjacent to the fused segment following anterior and posterior lumbar spine fusions at one, two and three levels (with and without instrumentation). RESULTS: It was found that instrumentation and length of fusion were the most significant factors in increasing adjacent level stresses in the lumbar discs. CONCLUSIONS: In the present study, a calibrated FE model that examined spinal interventions under similar loading and boundary conditions was used to provide quantitative data which would be useful for clinicians to understand the probable long-term effect of their choice of surgical intervention.

PCL-retaining versus PCL-substituting TKR - Outcome assessment based on the "forgotten joint score".

BACKGROUND: Posterior cruciate ligament (PCL) retention or sacrifice figures prominently among the current controversies in total knee arthroplasty (TKA). Even though biomechanical advantages and disadvantages have been claimed for each type of TKA, clinical studies have not shown significant differences in the outcomes. METHODS: In this retrospective study, the recently introduced "forgotten joint score" (FJS) was used to assess whether any differences exist between the two types of total knee replacement (TKR). FJ scores of 169 patients with PCL-retaining TKA and 178 patients with PCL sacrificing were obtained. The mean follow-up period was 3.5 years and the minimum follow-up period was 2.5 years. RESULTS: Both groups showed high FJ scores indicating that majority of the patients were oblivious to the presence of the artificial joint during daily activities. There was no statistically significant difference between the mean FJ scores of the two groups. Scores of subsets based on gender, age and unilateral and bilateral TKR also did not show significant differences. CONCLUSIONS: Since there are no clinically important differences between the two types of TKR, the choice of the TKA should be based on surgeon preferences and training and local conditions of the knee. Patient-reported outcomes appear to be similar regardless of the choice of TKA. Further prospective studies and validation of FJS outcomes with those of other questionnaires are essential to confirm the absence of differences between PCL retention and sacrifice.

Relative Contribution of Upper and Lower Lumbar Spinal Segments to Flexion/Extension: Comparison between Normal Spines and Spines with Disc Disease in Asian Patients.

STUDY DESIGN: Prospective cohort study. PURPOSE: To evaluate the contribution of upper and lower lumbar segments to flexion and extension of the lumbar spine in normal and diseased spines. OVERVIEW OF LITERATURE: The specific contributions of upper and lower lumbar segments during flexion/extension have rarely been reported. Furthermore, no comparisons between the flexion/extension behaviors of normal and diseased spines have been reported until now. METHODS: Flexion and extension lateral radiographs of 52 adult, asymptomatic volunteers, and 67 adult patients with lumbar spine disc disease were measured using software for total lumbar lordosis, upper lumbar lordosis and lower lumbar lordosis and the intervertebral angles of all segments. RESULTS: In asymptomatic volunteers, the range of movement between flexion and extension was a mean of only 4.2° in the lower lumbar spine and a mean of 19.4° in the upper lumbar spine. In patients with disc degeneration, the range of movement between flexion and extension was an average 6.5° for lower lumbar spine and 15.6° for the upper lumbar spine. CONCLUSIONS: The results showed that upper lumbar spine contributes more to the range of motion in flexion and extension than the lower lumbar spine in asymptomatic individuals without lumbar disc disease, as well as in patients with disc degeneration.

Calcar femorale grafting in the hemiarthroplasty of the hip for unstable inter trochanteric fractures.

BACKGROUND: The sliding screw-plate devices and cephalo-medullary nail devices have performed well in stable inter-trochanteric fractures in patients with reasonably good quality of bone. However, their suboptimal performance in comminuted fractures in the presence of osteoporotic bone has prompted many surgeons to consider bipolar hemiarthroplasty as the primary modality of management of comminuted inter-trochanteric fractures in elderly patients. However, long term stability of the hemiarthroplasty implant also may be compromised due to the presence of postero-medial bone loss at the area of the calcar. MATERIALS AND METHODS: We have presented a simple and effective technique of calcar grafting by harvesting cortical bone strut from the neck of the fractured femur. A total of 34 patients with inter-trochanteric fractures of the femur were treated with calcar grafting. The mean age was 79.2 years. The graft was harvested from the calcar region of the head and neck fragment of the femur and wedged between the medial femoral cortex and medial edge of the prosthesis. The mean followup period was 54.5 months. RESULTS: In 32 of 34 (94%) patients in our series, the calcar graft healed well without dislodgement. There was graft resorption in two patients associated with subsidence of the implant and loosening. CONCLUSION: Calcar grafting using this technique provides stability to the implant in the presence of comminution and incorporates well in the majority of patients. Donor site morbidity of graft harvesting is also avoided.

Patellar tendon or hamstring graft anterior cruciate ligament reconstructions in patients aged above 50 years.

BACKGROUND: The treatment of anterior cruciate ligament (ACL) injury consists of arthroscopic ACL reconstruction with patellar tendon or hamstring graft. Satisfactory results have been reported so far in the younger age group. Dilemma arises regarding the suitability of ACL reconstruction in patients aged 50 years and above. This retrospective analyses the outcome of ACL reconstruction in patients aged 50 years and above. MATERIALS AND METHODS: 55 patients aged 50 years and above presented to our institution with symptomatic ACL tear and were managed with arthroscopic reconstruction with patellar tendon/hamstring graft. 22 patients underwent ACL reconstruction with bone- patellar tendon-bone graft and the remaining 33 with a hamstring graft. Evaluation of functional outcome was performed using International Knee Documentation Committee (IKDC) and Lysholm scoring in the preoperative period, at the end of 1 year and at the final followup. Radiographic evaluation was performed using the Kellgren-Lawrence grading system. RESULTS: The mean preoperative IKDC score was 39.7 ± 3.3. At the end of 1-year following the operation, the mean IKDC score was 73.6 ± 4.9 and at the final followup was 67.8 ± 7.7. The mean preoperative Lysholm score was 40.4 ± 10.3. At the end of 1-year following the intervention, the mean Lysholm score was 89.7 ± 2.1 and at final followup was 85.3 ± 2.5. Overall, 14 out of 42 patients who underwent radiographic assessment showed progression of osteoarthritis changes at the final followup after the intervention. CONCLUSION: In our study, there was a statistically significant improvement in the IKDC and Lysholm scores following the intervention. There was a slight deterioration in the scores at the final followup but the overall rate of satisfaction was still high and most of the patients were able to do their routine chores and light exercises suitable for their age group. Around one-third of patients show progression of radiographic changes in the postoperative period and this requires long term evaluation.

Single locking compression plate fixation of extra-articular distal humeral fractures.

BACKGROUND: Earlier literature on fixation of distal third humeral fractures describes the use of elaborate modification of existing implants, custom-made implants and dual plating. These modifications have the disadvantages of limitations of hardware availability and cost as well as longer surgical exposure to accommodate the plates. The aim of this study was to assess the effectiveness of osteosynthesis of extra-articular diaphyseal fractures of the distal third of the humerus using a single 4.5-mm locking compression plate (LCP) with two-screw purchase in the distal fragment. MATERIALS AND METHODS: We performed internal fixation of distal third extra-articular humeral fractures in 22 adult patients using 2-3 lag screws neutralized with a single 4.5-mm locking compression plate with only two screws in the distal fragment. The mean follow-up period was approximately 1.6 years. RESULTS: Fractures united in all 22 patients with minimal complications. The mean time to union of fracture was 13 weeks. The Mayo elbow score and the DASH scores were in the excellent and good category in all patients at final follow-up. CONCLUSIONS: Our study showed that it is possible to obtain excellent outcomes in distal third fractures using only a single 4.5-mm LCP with two-screw (4-cortices) purchase in the distal fragment. The disadvantages inherent in the previous methods can be avoided with the use of the present technique. This technique obviates the need for the use of customized distal humeral implants and modified implants in most patients. LEVEL OF EVIDENCE: Level IV.

PET/CT study of temporal variations in blood flow to the femoral head following low-energy fracture of the femoral neck.

Earlier studies on femoral neck fractures have assessed the blood flow in either the pre- or postoperative period and information is lacking regarding changes in vascular flow to the femoral head after injury. Sixty-two adults with low-energy intracapsular femoral neck fractures were studied prospectively. Mean patient age was 57.2 years (range, 45-82 years). All patients underwent positron emission tomography/computed tomography (PET/CT) prior to surgical intervention and 6 weeks after internal fixation. Internal fixation was done using cannulated cancellous titanium screws and serial follow-up radiographs were obtained (at monthly intervals for the first 3 months followed by 3 monthly intervals between radiographs up to 2 years). On the preoperative PET/CT, 13 patients showed intact vascularity, 31 showed total loss of vascularity, and 18 showed partial loss of vascularity of the femoral head. The 6-week postoperative PET/CT scan showed recovery of blood supply in 23 of the 31 patients with total loss of vascularity and 15 of the 18 patients with partial loss of vascularity of the femoral head. Eleven of 62 patients had total or partial avascularity at the 6-week postoperative PET/CT scan and all 11 patients showed evidence of avascular necrosis on plain radiographs at the end of 2 years. The association between the vascular status of the femoral head at 6 weeks and avascular necrosis at the end of 2 years was statistically significant (P<.001). This study shows that the femoral head undergoes temporal variations in blood flow following femoral neck fracture. Decreased or absent vascularity is seen in approximately 75% of the fractures and 80% of the femoral heads with initial vascular compromise seem to regain blood flow within 6 weeks. Thus, prognostication about vascularity based on single-point preoperative imaging is difficult. The 6-week postoperative PET/CT scan seems to be reliable in predicting the future status of the femoral head. However, decision making regarding hemiarthroplasty or internal fixation at the time of injury may have to depend on factors other than the preoperative vascular status of the femoral head.

Positron emission tomography-computed tomography in the assessment of viability of femoral head in acetabular fractures.

PURPOSE: The aim of this study was to use positron emission tomography-computed tomography (PET-CT) imaging as a tool for assessment of viability of femoral head in acetabular fractures and help in early detection of complications like avascular necrosis (AVN) of the femoral head. METHODS: In our study PET-CT was done pre-operatively and six weeks postoperatively in 31 patients who underwent open reduction and internal fixation (ORIF) of acetabular fractures and fracture-dislocations. There were 26 male and five female patients who were treated in our institute between January 2009 and July 2010. Patients were subsequently followed up with plain radiographs for a mean period of 3.8 years and minimum of two years. RESULTS: Although seven out of 31 patients showed avascularity of the femoral head on PET-CT in the pre-operative period, only two patients progressed to AVN at final follow up, whereas the other five patients regained the vascularity at the end of six weeks. There was no statistically significant correlation between vascular status on pre-operative scan and the presence of AVN on final follow-up radiograph. There was a significant correlation between avascularity of the femoral head on the sixth week PET-CT and AVN in the final radiograph. CONCLUSION: PET-CT seems to be useful as a prognostic investigation in the assessment of the vascular status of the femoral head following injuries around the hip. Both pre-operative and postoperative imaging are necessary to understand the time-dependent changes in blood flow following injury.

Outcome of locking compression plates in humeral shaft nonunions.

BACKGROUND: Nonunion of diaphyseal fractures of the humerus are frequently seen in clinical practice (incidence of up to 15% in certain studies) and osteosynthesis using dynamic compression plates, intra medullary nails and Ilizarov fixators have been reported previously. Locking compression plates (LCP) are useful in the presence of disuse osteoporosis, segmental bone loss and cortical defects that preclude strong fixation. We report a prospective followup study of the outcome of the use of LCP for humeral nonunion following failed internal fixation in which implants other than LCP had been used. MATERIALS AND METHODS: Twenty four patients with nonunion of humeral shaft fractures following failed internal fixation were included in the study. The mean followup period was 3.4 years (range: 2.4 to 5.7 years) and the minimum followup period was 2 years. Mean age of the patients was 41.04 years (range: 24 to 57 years). All 24 patients underwent osteosynthesis using LCP and autologous bone grafting (cortico-cancellous iliac crest graft combined with or without fibular strut graft). Main outcome measurements included radiographic assessment of fracture union and pre and postoperative functional evaluation using the modified Constant and Murley scoring system. RESULTS: 23 out of 24 fractures united following osteosynthesis. Average time to union was 16 weeks (range: 10 to 28 weeks). Complications included delayed union (n = 2), transient radial nerve palsy (n = 2) and persistent nonunion (n = 1). Functional evaluation using the Constant and Murley score showed excellent results in 11, good in 10, fair in two and poor outcome in one patient. CONCLUSIONS: Locking compression plating and cancellous bone grafting is a reliable option for achieving union in humeral diaphyseal nonunion with failed previous internal fixation and results in good functional outcome in patients with higher physiological demands.

Isolated posterior instrumentation for selected cases of thoraco-lumbar spinal tuberculosis without anterior instrumentation and without anterior or posterior bone grafting.

PURPOSE: The aim of this prospective study is the analysis of the clinical and radiological outcomes of active thoraco-lumbar spinal tuberculosis treated with isolated posterior instrumentation without any posterior bone grafting or anterior inter-body bone grafting or anterior instrumentation. METHODS: The study was a prospective follow-up of 25 patients with active thoraco-lumbar spinal tuberculosis who underwent posterior spinal instrumentation with pedicle screws and rods. These patients had posterior stabilization of the involved segment of the spine without anterior or posterior bone grafting. The mean duration of follow-up was 3.3 years and the minimum duration of follow-up was 2 years. RESULTS: The mean kyphotic angle improved from 32.4° pre-operatively to 7.2° in the early follow-up period. Following a minor loss of correction during follow-up, the mean kyphotic angle settled at 11.5° at the time of final follow-up. Inter-body bony fusion was noticed at the final follow-up in all patients despite the absence of anterior bone grafting or cages. CONCLUSION: Posterior instrumented stabilization followed by chemotherapy seems to be adequate for obtaining satisfactory healing of the lesions. Anterior inter-body bony arthrodesis occurs despite the absence of anterior bone grafts or cages. Careful patient selection is critical for successful outcome with this technique.

A study on polyethylene stresses in mobile-bearing and fixed-bearing total knee arthroplasty (TKA) using explicit finite element analysis.

Mobile-bearing total knee arthroplasty designs were thought to be associated with lesser stresses on the polyethylene (PE) insert as compared to fixed-bearing designs. The wear rate of the PE liner was felt to be less in the mobile-bearing knees due to the decrease in the stresses. However, a reevaluation of the biomechanics of the mobile-bearing design is necessary due to the recent clinical reports on the long-term outcome of mobile-bearing knees which have not demonstrated any significant benefit in terms of implant survival and polyethylene wear rate. In this explicit finite element analysis of mobile-bearing and fixed-bearing knee designs using LS-DYNA, no significant differences have been found in the maximal stresses in the superior (articulating) surface of the PE insert in mobile- and fixed-bearing designs. On the inferior surface of the PE insert, the peak stresses were nearly 30% higher in the mobile-bearing compared with the fixed-bearing design. Thus, contrary to earlier expectations, mobile-bearing designs may be associated with higher overall PE stresses and wear than the fixed-bearing designs. Further research is necessary to minimize the wear rate of the PE insert in mobile-bearing total knee arthroplasty.